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<!--Created on: 8/5/2016 1:39:00 PM-->
<!--Modified on: 8/5/2016 1:39:00 PM-->
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_HeldToMaturitySecurities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Carrying Value</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AvailableForSaleSecurities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total Investment Securities</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_LoansAndLeasesReceivableAllowance_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Balance at the beginning of the period</label>
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LoansAndLeasesReceivableNetReportedAmount" xlink:to="us-gaap_LoansAndLeasesReceivableNetReportedAmount_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LoansAndLeasesReceivableNetReportedAmount_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loans and Leases Receivable, Net Amount</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_LoansAndLeasesReceivableNetReportedAmount_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net loans</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="us-gaap_PropertyPlantAndEquipmentNet" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PropertyPlantAndEquipmentNet" xlink:to="us-gaap_PropertyPlantAndEquipmentNet_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Property, Plant and Equipment, Net</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Bank premises and equipment, net</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InterestReceivable" xlink:label="us-gaap_InterestReceivable" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestReceivable" xlink:to="us-gaap_InterestReceivable_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestReceivable_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest Receivable</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestReceivable_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Accrued interest receivable</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherLongTermInvestments" xlink:label="us-gaap_OtherLongTermInvestments" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherLongTermInvestments" xlink:to="us-gaap_OtherLongTermInvestments_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherLongTermInvestments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other Long-term Investments</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherLongTermInvestments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other investments</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:to="us-gaap_IntangibleAssetsNetExcludingGoodwill_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Intangible Assets, Net (Excluding Goodwill)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Identified intangible assets, net</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_Goodwill" xlink:label="us-gaap_Goodwill" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_Goodwill" xlink:to="us-gaap_Goodwill_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_Goodwill_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Goodwill</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_Goodwill_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Goodwill</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherAssets" xlink:label="us-gaap_OtherAssets" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherAssets" xlink:to="us-gaap_OtherAssets_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherAssets_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other Assets</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherAssets_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other assets</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_Assets" xlink:label="us-gaap_Assets" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_Assets" xlink:to="us-gaap_Assets_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_Assets_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Assets</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_Assets_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total assets</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:to="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Liabilities and Equity [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Liabilities and Shareholders' Equity</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LiabilitiesAbstract" xlink:label="us-gaap_LiabilitiesAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesAbstract" xlink:to="us-gaap_LiabilitiesAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Liabilities [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LiabilitiesAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Liabilities:</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DepositsAbstract" xlink:label="us-gaap_DepositsAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DepositsAbstract" xlink:to="us-gaap_DepositsAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DepositsAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Deposits [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DepositsAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Deposits:</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DepositsAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Deposits</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NoninterestBearingDepositLiabilities" xlink:label="us-gaap_NoninterestBearingDepositLiabilities" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NoninterestBearingDepositLiabilities" xlink:to="us-gaap_NoninterestBearingDepositLiabilities_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NoninterestBearingDepositLiabilities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Noninterest-bearing Deposit Liabilities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NoninterestBearingDepositLiabilities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Demand - non-interest bearing</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InterestBearingDepositLiabilities" xlink:label="us-gaap_InterestBearingDepositLiabilities" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestBearingDepositLiabilities" xlink:to="us-gaap_InterestBearingDepositLiabilities_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestBearingDepositLiabilities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest-bearing Deposit Liabilities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestBearingDepositLiabilities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Savings and interest bearing demand</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_TimeDeposits" xlink:label="us-gaap_TimeDeposits" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TimeDeposits" xlink:to="us-gaap_TimeDeposits_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TimeDeposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Time Deposits</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TimeDeposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Time</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_TimeDeposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Carrying amount of time deposits</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_Deposits" xlink:label="us-gaap_Deposits" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_Deposits" xlink:to="us-gaap_Deposits_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_Deposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Deposits</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_Deposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total deposits</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_SecuritiesSoldUnderAgreementsToRepurchase" xlink:label="us-gaap_SecuritiesSoldUnderAgreementsToRepurchase" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SecuritiesSoldUnderAgreementsToRepurchase" xlink:to="us-gaap_SecuritiesSoldUnderAgreementsToRepurchase_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SecuritiesSoldUnderAgreementsToRepurchase_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Securities Sold under Agreements to Repurchase</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SecuritiesSoldUnderAgreementsToRepurchase_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Securities sold under repurchase agreements</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AdvancesFromFederalHomeLoanBanks" xlink:label="us-gaap_AdvancesFromFederalHomeLoanBanks" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AdvancesFromFederalHomeLoanBanks" xlink:to="us-gaap_AdvancesFromFederalHomeLoanBanks_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AdvancesFromFederalHomeLoanBanks_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Advances from Federal Home Loan Banks</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AdvancesFromFederalHomeLoanBanks_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other borrowed funds</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust" xlink:label="us-gaap_JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust" xlink:to="us-gaap_JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Junior subordinated deferrable interest debentures</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherLiabilities" xlink:label="us-gaap_OtherLiabilities" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherLiabilities" xlink:to="us-gaap_OtherLiabilities_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherLiabilities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other Liabilities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherLiabilities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other liabilities</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_Liabilities" xlink:label="us-gaap_Liabilities" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_Liabilities" xlink:to="us-gaap_Liabilities_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_Liabilities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Liabilities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_Liabilities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total liabilities</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StockholdersEquityAbstract" xlink:label="us-gaap_StockholdersEquityAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Stockholders' Equity Attributable to Parent [Abstract]</label>
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockholdersEquity" xlink:to="us-gaap_StockholdersEquity_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockholdersEquity_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Stockholders' Equity Attributable to Parent</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_StockholdersEquity_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total shareholders' equity</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesAndStockholdersEquity" xlink:to="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Liabilities and Equity</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total liabilities and shareholders' equity</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_HeldToMaturitySecuritiesFairValue" xlink:label="us-gaap_HeldToMaturitySecuritiesFairValue" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_HeldToMaturitySecuritiesFairValue" xlink:to="us-gaap_HeldToMaturitySecuritiesFairValue_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_HeldToMaturitySecuritiesFairValue_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Held-to-maturity Securities, Fair Value</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_HeldToMaturitySecuritiesFairValue_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Held to maturity, Market value (in dollars)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_HeldToMaturitySecuritiesFairValue_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Estimated Fair Value</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecuritiesAmortizedCost" xlink:label="us-gaap_AvailableForSaleSecuritiesAmortizedCost" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AvailableForSaleSecuritiesAmortizedCost" xlink:to="us-gaap_AvailableForSaleSecuritiesAmortizedCost_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AvailableForSaleSecuritiesAmortizedCost_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Available-for-sale Securities, Amortized Cost Basis</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AvailableForSaleSecuritiesAmortizedCost_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Available for sale, Amortized cost (in dollars)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_AvailableForSaleSecuritiesAmortizedCost_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Amortized cost, Available for sale securities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_AvailableForSaleSecuritiesAmortizedCost_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Amortized Cost</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockParOrStatedValuePerShare" xlink:to="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Common Stock, Par or Stated Value Per Share</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Common shares, par value (in dollars per share)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="us-gaap_CommonStockSharesAuthorized" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockSharesAuthorized" xlink:to="us-gaap_CommonStockSharesAuthorized_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Common Stock, Shares Authorized</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Common shares, Authorized shares</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CommonStockSharesIssued" xlink:label="us-gaap_CommonStockSharesIssued" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Common Stock, Shares, Issued</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Common shares, issued shares</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxDebtSecurities" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxDebtSecurities" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxDebtSecurities" xlink:to="us-gaap_AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxDebtSecurities_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxDebtSecurities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Accumulated Other Comprehensive Income (Loss), Other than Temporary Impairment, Not Credit Loss, Net of Tax, Debt Securities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxDebtSecurities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Comprehensive loss related to other-than-temporary impairment for non-credit related issues (in dollars)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_TreasuryStockShares" xlink:label="us-gaap_TreasuryStockShares" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TreasuryStockShares" xlink:to="us-gaap_TreasuryStockShares_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TreasuryStockShares_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Treasury Stock, Shares</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TreasuryStockShares_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Treasury, shares</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncomeStatementAbstract" xlink:label="us-gaap_IncomeStatementAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_IncomeStatementAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeStatementAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Consolidated Statements of Income</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InterestAndDividendIncomeOperatingAbstract" xlink:label="us-gaap_InterestAndDividendIncomeOperatingAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestAndDividendIncomeOperatingAbstract" xlink:to="us-gaap_InterestAndDividendIncomeOperatingAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestAndDividendIncomeOperatingAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest and Dividend Income, Operating [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestAndDividendIncomeOperatingAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest income:</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InterestAndFeeIncomeLoansAndLeases" xlink:label="us-gaap_InterestAndFeeIncomeLoansAndLeases" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestAndFeeIncomeLoansAndLeases_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest and Fee Income, Loans and Leases</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestAndFeeIncomeLoansAndLeases_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loans, including fees</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InterestAndDividendIncomeSecuritiesByTaxableStatusAbstract" xlink:label="us-gaap_InterestAndDividendIncomeSecuritiesByTaxableStatusAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestAndDividendIncomeSecuritiesByTaxableStatusAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest and Dividend Income, Securities, by Taxable Status [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestAndDividendIncomeSecuritiesByTaxableStatusAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Investment securities:</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestIncomeSecuritiesTaxable_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Taxable</label>
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestIncomeSecuritiesTaxExempt" xlink:to="us-gaap_InterestIncomeSecuritiesTaxExempt_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestIncomeSecuritiesTaxExempt_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest Income, Securities, Operating, Tax Exempt</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestIncomeSecuritiesTaxExempt_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Tax-exempt</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherInterestAndDividendIncome" xlink:label="us-gaap_OtherInterestAndDividendIncome" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherInterestAndDividendIncome" xlink:to="us-gaap_OtherInterestAndDividendIncome_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherInterestAndDividendIncome_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other Interest and Dividend Income</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherInterestAndDividendIncome_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other interest income</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InterestAndDividendIncomeOperating" xlink:label="us-gaap_InterestAndDividendIncomeOperating" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestAndDividendIncomeOperating" xlink:to="us-gaap_InterestAndDividendIncomeOperating_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestAndDividendIncomeOperating_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest and Dividend Income, Operating</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_InterestAndDividendIncomeOperating_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total interest income</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InterestExpenseAbstract" xlink:label="us-gaap_InterestExpenseAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestExpenseAbstract" xlink:to="us-gaap_InterestExpenseAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestExpenseAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest Expense [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestExpenseAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest expense:</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InterestExpenseNOWAccountsMoneyMarketAccountsAndSavingsDeposits" xlink:label="us-gaap_InterestExpenseNOWAccountsMoneyMarketAccountsAndSavingsDeposits" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestExpenseNOWAccountsMoneyMarketAccountsAndSavingsDeposits" xlink:to="us-gaap_InterestExpenseNOWAccountsMoneyMarketAccountsAndSavingsDeposits_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestExpenseNOWAccountsMoneyMarketAccountsAndSavingsDeposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest Expense, NOW Accounts, Money Market Accounts, and Savings Deposits</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestExpenseNOWAccountsMoneyMarketAccountsAndSavingsDeposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Savings deposits</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InterestExpenseTimeDeposits" xlink:label="us-gaap_InterestExpenseTimeDeposits" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestExpenseTimeDeposits" xlink:to="us-gaap_InterestExpenseTimeDeposits_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestExpenseTimeDeposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest Expense, Time Deposits</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestExpenseTimeDeposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Time deposits</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InterestExpenseSecuritiesSoldUnderAgreementsToRepurchase" xlink:label="us-gaap_InterestExpenseSecuritiesSoldUnderAgreementsToRepurchase" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestExpenseSecuritiesSoldUnderAgreementsToRepurchase" xlink:to="us-gaap_InterestExpenseSecuritiesSoldUnderAgreementsToRepurchase_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestExpenseSecuritiesSoldUnderAgreementsToRepurchase_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest Expense, Securities Sold under Agreements to Repurchase</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestExpenseSecuritiesSoldUnderAgreementsToRepurchase_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Securities sold under repurchase agreements</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_InterestExpenseOtherBorrowings" xlink:label="iboc_InterestExpenseOtherBorrowings" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_InterestExpenseOtherBorrowings" xlink:to="iboc_InterestExpenseOtherBorrowings_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_InterestExpenseOtherBorrowings_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest expense incurred during the reporting period on other borrowings not defined elsewhere in the taxonomy. Includes interest expense incurred on both the short-term and long-term borrowings (advances) with the Federal Home Loan Bank and other short term borrowings.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_InterestExpenseOtherBorrowings_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest Expense Other Borrowings</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_InterestExpenseOtherBorrowings_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other borrowings</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InterestExpenseJuniorSubordinatedDebentures" xlink:label="us-gaap_InterestExpenseJuniorSubordinatedDebentures" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestExpenseJuniorSubordinatedDebentures" xlink:to="us-gaap_InterestExpenseJuniorSubordinatedDebentures_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestExpenseJuniorSubordinatedDebentures_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Junior subordinated deferrable interest debentures, interest</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestExpenseJuniorSubordinatedDebentures_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Junior subordinated deferrable interest debentures</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InterestExpense" xlink:label="us-gaap_InterestExpense" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestExpense" xlink:to="us-gaap_InterestExpense_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestExpense_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest Expense</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_InterestExpense_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total interest expense</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InterestIncomeExpenseNet" xlink:label="us-gaap_InterestIncomeExpenseNet" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestIncomeExpenseNet" xlink:to="us-gaap_InterestIncomeExpenseNet_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestIncomeExpenseNet_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest Income (Expense), Net</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_InterestIncomeExpenseNet_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net interest income</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ProvisionForLoanAndLeaseLosses" xlink:label="us-gaap_ProvisionForLoanAndLeaseLosses" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProvisionForLoanAndLeaseLosses" xlink:to="us-gaap_ProvisionForLoanAndLeaseLosses_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProvisionForLoanAndLeaseLosses_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Provision for Loan and Lease Losses</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProvisionForLoanAndLeaseLosses_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Provision for probable loan losses</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ProvisionForLoanAndLeaseLosses_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Provision charged to operations</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss" xlink:label="us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss" xlink:to="us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest Income (Expense), after Provision for Loan Loss</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net interest income after provision for probable loan losses</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NoninterestIncomeAbstract" xlink:label="us-gaap_NoninterestIncomeAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NoninterestIncomeAbstract" xlink:to="us-gaap_NoninterestIncomeAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NoninterestIncomeAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Noninterest Income [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NoninterestIncomeAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Non-interest income:</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FeesAndCommissionsDepositorAccounts" xlink:label="us-gaap_FeesAndCommissionsDepositorAccounts" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FeesAndCommissionsDepositorAccounts" xlink:to="us-gaap_FeesAndCommissionsDepositorAccounts_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FeesAndCommissionsDepositorAccounts_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fees and Commissions, Depositor Accounts</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FeesAndCommissionsDepositorAccounts_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Service charges on deposit accounts</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_OtherServiceChargesCommissionsAndFeesAbstract" xlink:label="iboc_OtherServiceChargesCommissionsAndFeesAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_OtherServiceChargesCommissionsAndFeesAbstract" xlink:to="iboc_OtherServiceChargesCommissionsAndFeesAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_OtherServiceChargesCommissionsAndFeesAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other Service Charges, Commissions and Fees [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_OtherServiceChargesCommissionsAndFeesAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other service charges, commissions and fees</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_ServiceChargesFeesAndCommissionsOtherBanking" xlink:label="iboc_ServiceChargesFeesAndCommissionsOtherBanking" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_ServiceChargesFeesAndCommissionsOtherBanking" xlink:to="iboc_ServiceChargesFeesAndCommissionsOtherBanking_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_ServiceChargesFeesAndCommissionsOtherBanking_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Service charges, fees, and commission's revenue earned from banking operations, other than from deposit accounts.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_ServiceChargesFeesAndCommissionsOtherBanking_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Service Charges, Fees and Commissions, Other, Banking</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_ServiceChargesFeesAndCommissionsOtherBanking_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Banking</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FeesAndCommissionsOther" xlink:label="us-gaap_FeesAndCommissionsOther" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FeesAndCommissionsOther" xlink:to="us-gaap_FeesAndCommissionsOther_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FeesAndCommissionsOther_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fees and Commissions, Other</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FeesAndCommissionsOther_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Non-banking</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_GainLossOnSaleOfSecuritiesNet" xlink:label="us-gaap_GainLossOnSaleOfSecuritiesNet" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_GainLossOnSaleOfSecuritiesNet" xlink:to="us-gaap_GainLossOnSaleOfSecuritiesNet_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_GainLossOnSaleOfSecuritiesNet_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Gain (Loss) on Sale of Securities, Net</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_GainLossOnSaleOfSecuritiesNet_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Investment securities transactions, net</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_GainLossOnSaleOfSecuritiesNet_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Investment securities transactions, net</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NoninterestIncomeOther" xlink:label="us-gaap_NoninterestIncomeOther" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NoninterestIncomeOther" xlink:to="us-gaap_NoninterestIncomeOther_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NoninterestIncomeOther_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Noninterest Income, Other</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NoninterestIncomeOther_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other investments, net</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NoninterestIncomeOtherOperatingIncome" xlink:label="us-gaap_NoninterestIncomeOtherOperatingIncome" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NoninterestIncomeOtherOperatingIncome" xlink:to="us-gaap_NoninterestIncomeOtherOperatingIncome_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NoninterestIncomeOtherOperatingIncome_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Noninterest Income, Other Operating Income</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NoninterestIncomeOtherOperatingIncome_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other income</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NoninterestIncome" xlink:label="us-gaap_NoninterestIncome" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NoninterestIncome" xlink:to="us-gaap_NoninterestIncome_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NoninterestIncome_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total non-interest income</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NoninterestExpenseAbstract" xlink:label="us-gaap_NoninterestExpenseAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NoninterestExpenseAbstract" xlink:to="us-gaap_NoninterestExpenseAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NoninterestExpenseAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Noninterest Expense [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NoninterestExpenseAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Non-interest expense:</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LaborAndRelatedExpense" xlink:label="us-gaap_LaborAndRelatedExpense" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LaborAndRelatedExpense" xlink:to="us-gaap_LaborAndRelatedExpense_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LaborAndRelatedExpense_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Labor and Related Expense</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LaborAndRelatedExpense_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Employee compensation and benefits</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OccupancyNet" xlink:label="us-gaap_OccupancyNet" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OccupancyNet" xlink:to="us-gaap_OccupancyNet_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OccupancyNet_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Occupancy, Net</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OccupancyNet_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Occupancy</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DepreciationNonproduction" xlink:label="us-gaap_DepreciationNonproduction" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DepreciationNonproduction" xlink:to="us-gaap_DepreciationNonproduction_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DepreciationNonproduction_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Depreciation, Nonproduction</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DepreciationNonproduction_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Depreciation of bank premises and equipment</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ProfessionalFees" xlink:label="us-gaap_ProfessionalFees" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProfessionalFees" xlink:to="us-gaap_ProfessionalFees_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProfessionalFees_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Professional Fees</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProfessionalFees_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Professional fees</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FederalDepositInsuranceCorporationPremiumExpense" xlink:label="us-gaap_FederalDepositInsuranceCorporationPremiumExpense" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FederalDepositInsuranceCorporationPremiumExpense" xlink:to="us-gaap_FederalDepositInsuranceCorporationPremiumExpense_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FederalDepositInsuranceCorporationPremiumExpense_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Federal Deposit Insurance Corporation Premium Expense</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FederalDepositInsuranceCorporationPremiumExpense_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Deposit insurance assessments</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherRevenueExpenseFromRealEstateOperations" xlink:label="us-gaap_OtherRevenueExpenseFromRealEstateOperations" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherRevenueExpenseFromRealEstateOperations" xlink:to="us-gaap_OtherRevenueExpenseFromRealEstateOperations_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherRevenueExpenseFromRealEstateOperations_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other Revenue (Expense) from Real Estate Operations</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_OtherRevenueExpenseFromRealEstateOperations_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net expense, other real estate owned</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AmortizationOfIntangibleAssets" xlink:label="us-gaap_AmortizationOfIntangibleAssets" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AmortizationOfIntangibleAssets" xlink:to="us-gaap_AmortizationOfIntangibleAssets_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Amortization of Intangible Assets</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Amortization of identified intangible assets</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AdvertisingExpense" xlink:label="us-gaap_AdvertisingExpense" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AdvertisingExpense" xlink:to="us-gaap_AdvertisingExpense_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AdvertisingExpense_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Advertising Expense</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AdvertisingExpense_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Advertising</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InformationTechnologyAndDataProcessing" xlink:label="us-gaap_InformationTechnologyAndDataProcessing" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InformationTechnologyAndDataProcessing" xlink:to="us-gaap_InformationTechnologyAndDataProcessing_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InformationTechnologyAndDataProcessing_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Information Technology and Data Processing</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InformationTechnologyAndDataProcessing_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Software and software maintenance</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet" xlink:label="us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet" xlink:to="us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impairment charges on available for sale securities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impairment charges on available for sale securities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impairment charges (Total other-than-temporary impairment charges, $(300) net of $(367), and $(54), net of $(278), $(332) net of $(523) and $(176), net of $(627), included in other comprehensive income)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherNoninterestExpense" xlink:label="us-gaap_OtherNoninterestExpense" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherNoninterestExpense" xlink:to="us-gaap_OtherNoninterestExpense_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherNoninterestExpense_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other Noninterest Expense</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherNoninterestExpense_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NoninterestExpense" xlink:label="us-gaap_NoninterestExpense" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NoninterestExpense" xlink:to="us-gaap_NoninterestExpense_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NoninterestExpense_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Noninterest Expense</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NoninterestExpense_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total non-interest expense</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:to="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Income before income taxes</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="us-gaap_IncomeTaxExpenseBenefit" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxExpenseBenefit" xlink:to="us-gaap_IncomeTaxExpenseBenefit_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Income Tax Expense (Benefit)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Provision for income taxes</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="us-gaap_NetIncomeLoss" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetIncomeLoss" xlink:to="us-gaap_NetIncomeLoss_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetIncomeLoss_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net Income (Loss) Attributable to Parent</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NetIncomeLoss_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net income</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetIncomeLoss_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net income</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_EarningsPerShareBasicAbstract" xlink:label="us-gaap_EarningsPerShareBasicAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EarningsPerShareBasicAbstract" xlink:to="us-gaap_EarningsPerShareBasicAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EarningsPerShareBasicAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Earnings Per Share, Basic [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EarningsPerShareBasicAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Basic earnings per common share:</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Operating activities:</label>
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:to="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Adjustments to reconcile net income to net cash provided by operating activities:</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherRealEstateCoveredValuationAdjustments" xlink:label="us-gaap_OtherRealEstateCoveredValuationAdjustments" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherRealEstateCoveredValuationAdjustments" xlink:to="us-gaap_OtherRealEstateCoveredValuationAdjustments_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherRealEstateCoveredValuationAdjustments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other Real Estate, Covered, Valuation Adjustments</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_OtherRealEstateCoveredValuationAdjustments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Specific reserve, other real estate owned</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_GainLossOnSaleOfPropertyPlantEquipment" xlink:label="us-gaap_GainLossOnSaleOfPropertyPlantEquipment" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_GainLossOnSaleOfPropertyPlantEquipment" xlink:to="us-gaap_GainLossOnSaleOfPropertyPlantEquipment_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_GainLossOnSaleOfPropertyPlantEquipment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Gain (Loss) on Disposition of Property Plant Equipment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_GainLossOnSaleOfPropertyPlantEquipment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Gain on sale of bank premises and equipment</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_GainsLossesOnSalesOfOtherRealEstate" xlink:label="us-gaap_GainsLossesOnSalesOfOtherRealEstate" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_GainsLossesOnSalesOfOtherRealEstate" xlink:to="us-gaap_GainsLossesOnSalesOfOtherRealEstate_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_GainsLossesOnSalesOfOtherRealEstate_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Gains (Losses) on Sales of Other Real Estate</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_GainsLossesOnSalesOfOtherRealEstate_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Gain on sale of other real estate owned</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_AccretionOfDiscountsInvestments" xlink:label="iboc_AccretionOfDiscountsInvestments" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_AccretionOfDiscountsInvestments" xlink:to="iboc_AccretionOfDiscountsInvestments_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_AccretionOfDiscountsInvestments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">The periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings when the security was purchased at a discount. As a noncash item, this element is an adjustment to net income when calculating cash provided by (used in) operations using the indirect method.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_AccretionOfDiscountsInvestments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Accretion of Discounts Investments</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="iboc_AccretionOfDiscountsInvestments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Accretion of investment securities discounts</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_AmortizationOfInvestmentSecuritiesPremiums" xlink:label="iboc_AmortizationOfInvestmentSecuritiesPremiums" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_AmortizationOfInvestmentSecuritiesPremiums" xlink:to="iboc_AmortizationOfInvestmentSecuritiesPremiums_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_AmortizationOfInvestmentSecuritiesPremiums_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">The periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings when the security was purchased at a premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by (used in) operations using the indirect method.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_AmortizationOfInvestmentSecuritiesPremiums_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Amortization of Investment Securities Premiums</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_AmortizationOfInvestmentSecuritiesPremiums_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Amortization of investment securities premiums</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensation" xlink:label="us-gaap_ShareBasedCompensation" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensation" xlink:to="us-gaap_ShareBasedCompensation_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensation_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Share-based Compensation</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ShareBasedCompensation_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Stock based compensation expense</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncomeLossFromEquityMethodInvestments" xlink:label="us-gaap_IncomeLossFromEquityMethodInvestments" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeLossFromEquityMethodInvestments" xlink:to="us-gaap_IncomeLossFromEquityMethodInvestments_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeLossFromEquityMethodInvestments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Income (Loss) from Equity Method Investments</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_IncomeLossFromEquityMethodInvestments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Earnings from affiliates and other investments</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:to="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Deferred Income Tax Expense (Benefit)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Deferred tax expense</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncreaseDecreaseInAccruedInterestReceivableNet" xlink:label="us-gaap_IncreaseDecreaseInAccruedInterestReceivableNet" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInAccruedInterestReceivableNet" xlink:to="us-gaap_IncreaseDecreaseInAccruedInterestReceivableNet_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInAccruedInterestReceivableNet_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Increase (Decrease) in Accrued Interest Receivable, Net</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_IncreaseDecreaseInAccruedInterestReceivableNet_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Decrease in accrued interest receivable</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncreaseDecreaseInOtherOperatingAssets" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingAssets" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInOtherOperatingAssets" xlink:to="us-gaap_IncreaseDecreaseInOtherOperatingAssets_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingAssets_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Increase (Decrease) in Other Operating Assets</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingAssets_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Increase in other assets</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncreaseDecreaseInOtherOperatingLiabilities" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingLiabilities" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInOtherOperatingLiabilities" xlink:to="us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Increase (Decrease) in Other Operating Liabilities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Decrease in other liabilities</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net Cash Provided by (Used in) Operating Activities, Continuing Operations</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net cash (used in) provided by operating activities</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Investing activities:</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfOtherInvestments" xlink:label="us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfOtherInvestments" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfOtherInvestments" xlink:to="us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfOtherInvestments_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfOtherInvestments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Proceeds from maturities of securities</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities" xlink:label="us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities" xlink:to="us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Proceeds from Sale of Available-for-sale Securities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Proceeds from sales and calls of available for sale securities</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PaymentsToAcquireAvailableForSaleSecurities" xlink:label="us-gaap_PaymentsToAcquireAvailableForSaleSecurities" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsToAcquireAvailableForSaleSecurities" xlink:to="us-gaap_PaymentsToAcquireAvailableForSaleSecurities_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PaymentsToAcquireAvailableForSaleSecurities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Payments to Acquire Available-for-sale Securities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_PaymentsToAcquireAvailableForSaleSecurities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Purchases of available for sale securities</label>
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities" xlink:to="us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Principal collected on mortgage-backed securities</label>
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsForProceedsFromLoansAndLeases" xlink:to="us-gaap_PaymentsForProceedsFromLoansAndLeases_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PaymentsForProceedsFromLoansAndLeases_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Payments for (Proceeds from) Loans and Leases</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_PaymentsForProceedsFromLoansAndLeases_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net increase in loans</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PaymentsToAcquireOtherInvestments" xlink:label="us-gaap_PaymentsToAcquireOtherInvestments" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsToAcquireOtherInvestments" xlink:to="us-gaap_PaymentsToAcquireOtherInvestments_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PaymentsToAcquireOtherInvestments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Payments to Acquire Other Investments</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_PaymentsToAcquireOtherInvestments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Purchases of other investments</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_DistributionsFromOtherInvestments" xlink:label="iboc_DistributionsFromOtherInvestments" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_DistributionsFromOtherInvestments" xlink:to="iboc_DistributionsFromOtherInvestments_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_DistributionsFromOtherInvestments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Cash inflows from other investments. Includes distributions from equity method investments plus other cash inflows from investments not individually reported.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_DistributionsFromOtherInvestments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Distributions from Other Investments</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_DistributionsFromOtherInvestments_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Distributions from other investments</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:to="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Payments to Acquire Property, Plant, and Equipment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Purchases of bank premises and equipment</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:label="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:to="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Proceeds from Sale of Property, Plant, and Equipment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Proceeds from sales of bank premises and equipment</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ProceedsFromSaleOfOtherRealEstate" xlink:label="us-gaap_ProceedsFromSaleOfOtherRealEstate" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromSaleOfOtherRealEstate" xlink:to="us-gaap_ProceedsFromSaleOfOtherRealEstate_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromSaleOfOtherRealEstate_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Proceeds from Sale of Other Real Estate</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProceedsFromSaleOfOtherRealEstate_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Proceeds from sales of other real estate owned</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net Cash Provided by (Used in) Investing Activities, Continuing Operations</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net cash provided by investing activities</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing activities:</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_IncreaseDecreaseInNoninterestBearingDemandDeposits" xlink:label="iboc_IncreaseDecreaseInNoninterestBearingDemandDeposits" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_IncreaseDecreaseInNoninterestBearingDemandDeposits" xlink:to="iboc_IncreaseDecreaseInNoninterestBearingDemandDeposits_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_IncreaseDecreaseInNoninterestBearingDemandDeposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">The net cash inflow (outflow) in the total of all Noninterest-bearing demand deposits classified as cash flows from financing activities.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_IncreaseDecreaseInNoninterestBearingDemandDeposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Increase (Decrease) in Noninterest Bearing Demand Deposits</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_IncreaseDecreaseInNoninterestBearingDemandDeposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net (decrease) increase in non-interest bearing demand deposits</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_IncreaseDecreaseInSavingAndInterestBearingDemandDeposits" xlink:label="iboc_IncreaseDecreaseInSavingAndInterestBearingDemandDeposits" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_IncreaseDecreaseInSavingAndInterestBearingDemandDeposits" xlink:to="iboc_IncreaseDecreaseInSavingAndInterestBearingDemandDeposits_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_IncreaseDecreaseInSavingAndInterestBearingDemandDeposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">The net cash inflow (outflow) in the total of all interest bearing deposit accounts, classified as cash flows from financing activities.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_IncreaseDecreaseInSavingAndInterestBearingDemandDeposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Increase (Decrease) in Saving and Interest Bearing Demand Deposits</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_IncreaseDecreaseInSavingAndInterestBearingDemandDeposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net increase (decrease) in savings and interest bearing demand deposits</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncreaseDecreaseInTimeDeposits" xlink:label="us-gaap_IncreaseDecreaseInTimeDeposits" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInTimeDeposits" xlink:to="us-gaap_IncreaseDecreaseInTimeDeposits_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInTimeDeposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Increase (Decrease) in Time Deposits</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncreaseDecreaseInTimeDeposits_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net decrease in time deposits</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase" xlink:label="us-gaap_ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase" xlink:to="us-gaap_ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Proceeds from (Payments for) in Securities Sold under Agreements to Repurchase</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net (decrease) increase in securities sold under repurchase agreements</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncreaseDecreaseInLoansFromOtherFederalHomeLoanBanks" xlink:label="us-gaap_IncreaseDecreaseInLoansFromOtherFederalHomeLoanBanks" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInLoansFromOtherFederalHomeLoanBanks" xlink:to="us-gaap_IncreaseDecreaseInLoansFromOtherFederalHomeLoanBanks_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInLoansFromOtherFederalHomeLoanBanks_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Increase (Decrease) in Loans from Federal Home Loan Banks</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncreaseDecreaseInLoansFromOtherFederalHomeLoanBanks_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net increase (decrease) in other borrowed funds</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock" xlink:label="us-gaap_PaymentsForRepurchaseOfCommonStock" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsForRepurchaseOfCommonStock" xlink:to="us-gaap_PaymentsForRepurchaseOfCommonStock_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PaymentsForRepurchaseOfCommonStock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Payments for Repurchase of Common Stock</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_PaymentsForRepurchaseOfCommonStock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Purchase of treasury stock</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ProceedsFromIssuanceOrSaleOfEquity" xlink:label="us-gaap_ProceedsFromIssuanceOrSaleOfEquity" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromIssuanceOrSaleOfEquity" xlink:to="us-gaap_ProceedsFromIssuanceOrSaleOfEquity_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromIssuanceOrSaleOfEquity_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Proceeds from Issuance or Sale of Equity</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProceedsFromIssuanceOrSaleOfEquity_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Proceeds from stock transactions</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PaymentsOfDividendsCommonStock" xlink:label="us-gaap_PaymentsOfDividendsCommonStock" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsOfDividendsCommonStock" xlink:to="us-gaap_PaymentsOfDividendsCommonStock_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PaymentsOfDividendsCommonStock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Payments of Ordinary Dividends, Common Stock</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_PaymentsOfDividendsCommonStock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Payments of cash dividends - common</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net Cash Provided by (Used in) Financing Activities, Continuing Operations</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net cash used in financing activities</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInContinuingOperations" xlink:label="us-gaap_NetCashProvidedByUsedInContinuingOperations" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInContinuingOperations" xlink:to="us-gaap_NetCashProvidedByUsedInContinuingOperations_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInContinuingOperations_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net Cash Provided by (Used in) Continuing Operations</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetCashProvidedByUsedInContinuingOperations_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">(Decrease) increase in cash and cash equivalents</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_SupplementalCashFlowInformationAbstract" xlink:label="us-gaap_SupplementalCashFlowInformationAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_BasisOfPresentationDisclosureAbstract" xlink:to="iboc_BasisOfPresentationDisclosureAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_BasisOfPresentationTextBlock" xlink:to="iboc_BasisOfPresentationTextBlock_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_BasisOfPresentationTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">This element represents the entire disclosure regarding basis of presentation.</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FairValueDisclosuresTextBlock" xlink:label="us-gaap_FairValueDisclosuresTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LoansNotesTradeAndOtherReceivablesDisclosureTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loans</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_AllowanceForProbableLoanLossesDisclosureAbstract" xlink:label="iboc_AllowanceForProbableLoanLossesDisclosureAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_AllowanceForProbableLoanLossesDisclosureAbstract" xlink:to="iboc_AllowanceForProbableLoanLossesDisclosureAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AllowanceForCreditLossesTextBlock" xlink:label="us-gaap_AllowanceForCreditLossesTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AllowanceForCreditLossesTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Allowance for Probable Loan Losses</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Stock Options</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract" xlink:label="us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock" xlink:label="us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FederalHomeLoanBankAdvancesDisclosureTextBlock" xlink:label="us-gaap_FederalHomeLoanBankAdvancesDisclosureTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_SubordinatedBorrowingsDisclosureTextBlock" xlink:label="us-gaap_SubordinatedBorrowingsDisclosureTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock" xlink:label="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock" xlink:to="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Assets and liabilities measured at fair value on a recurring basis</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock" xlink:to="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Reconciliation of activity for mortgage-backed securities on a net basis</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnNonrecurringBasisTextBlock" xlink:label="us-gaap_FairValueAssetsMeasuredOnNonrecurringBasisTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueAssetsMeasuredOnNonrecurringBasisTextBlock" xlink:to="us-gaap_FairValueAssetsMeasuredOnNonrecurringBasisTextBlock_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueAssetsMeasuredOnNonrecurringBasisTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value Measurements, Nonrecurring [Table Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueAssetsMeasuredOnNonrecurringBasisTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Assets measured at fair value on a non-recurring basis</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock" xlink:label="us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock" xlink:to="us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Summary of loans, by loan type</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfCreditLossesRelatedToFinancingReceivablesCurrentAndNoncurrentTableTextBlock" xlink:label="us-gaap_ScheduleOfCreditLossesRelatedToFinancingReceivablesCurrentAndNoncurrentTableTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfCreditLossesRelatedToFinancingReceivablesCurrentAndNoncurrentTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Schedule of Credit Losses Related to Financing Receivables, Current and Noncurrent [Table Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ScheduleOfCreditLossesRelatedToFinancingReceivablesCurrentAndNoncurrentTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Summary of the transactions in the allowance for probable loan losses by loan class</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock" xlink:label="us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock" xlink:to="us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Allowance for Credit Losses on Financing Receivables [Table Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loans individually or collectively evaluated for their impairment and related allowance, by loan class</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfFinancingReceivablesNonAccrualStatusTableTextBlock" xlink:label="us-gaap_ScheduleOfFinancingReceivablesNonAccrualStatusTableTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfFinancingReceivablesNonAccrualStatusTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Schedule of Financing Receivables, Non Accrual Status [Table Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ScheduleOfFinancingReceivablesNonAccrualStatusTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loans accounted on non-accrual basis, by loan class</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ImpairedFinancingReceivablesTableTextBlock" xlink:label="us-gaap_ImpairedFinancingReceivablesTableTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ImpairedFinancingReceivablesTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired Financing Receivables [Table Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ImpairedFinancingReceivablesTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired loans, by loan class</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_TroubledDebtRestructuringsOnFinancingReceivablesTableTextBlock" xlink:label="us-gaap_TroubledDebtRestructuringsOnFinancingReceivablesTableTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TroubledDebtRestructuringsOnFinancingReceivablesTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Troubled Debt Restructurings on Financing Receivables [Table Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TroubledDebtRestructuringsOnFinancingReceivablesTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loans accounted for as trouble debt restructuring, by loan class</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PastDueFinancingReceivablesTableTextBlock" xlink:label="us-gaap_PastDueFinancingReceivablesTableTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PastDueFinancingReceivablesTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Information regarding the aging of past due loans, by loan class</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock" xlink:label="us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivable Credit Quality Indicators [Table Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Summary of the loan portfolio by credit quality indicator, by loan class</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock" xlink:label="us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Summary of option activity under stock option plans</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/invest/2013/invest-2013-01-31.xsd#invest_InvestmentTableTextBlock" xlink:label="invest_InvestmentTableTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="invest_InvestmentTableTextBlock" xlink:to="invest_InvestmentTableTextBlock_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="invest_InvestmentTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Investment [Table Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="invest_InvestmentTableTextBlock_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Amortized cost and estimated fair value by type of investment security</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock" xlink:label="us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FairValueByMeasurementFrequencyAxis" xlink:label="us-gaap_FairValueByMeasurementFrequencyAxis" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:to="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value Measurements Fair Value Hierarchy [Domain]</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FairValueInputsLevel1Member" xlink:label="us-gaap_FairValueInputsLevel1Member" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueInputsLevel1Member" xlink:to="us-gaap_FairValueInputsLevel1Member_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value Inputs Level1 [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Quoted Prices in Active Markets for Identical Assets (Level 1)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FairValueInputsLevel2Member" xlink:label="us-gaap_FairValueInputsLevel2Member" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueInputsLevel2Member" xlink:to="us-gaap_FairValueInputsLevel2Member_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueInputsLevel2Member_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value Inputs Level2 [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueInputsLevel2Member_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Significant Other Observable Inputs (Level 2)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FairValueInputsLevel3Member" xlink:label="us-gaap_FairValueInputsLevel3Member" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueInputsLevel3Member" xlink:to="us-gaap_FairValueInputsLevel3Member_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value Inputs Level3 [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Significant Unobservable Inputs (Level 3)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Major Types of Debt and Equity Securities [Axis]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MortgageBackedSecuritiesMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Mortgage Backed Securities [Member]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value, Assets Measured on Recurring Basis, mortgage-backed securities reconciliation</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Reconciliation of activity for mortgage-backed securities on a net basis</label>
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue" xlink:to="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Balance at the end of the period</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Balance at the beginning of the period</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements" xlink:to="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Principal paydowns</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossAbstract" xlink:label="iboc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total unrealized gains or losses included abstract.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Gain (Loss) [Abstract]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other comprehensive income</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_BondMeetingOriginalContractTermsMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Represents the portion of the bond where the underlying residential mortgage had not been meeting the original contract terms for at least 24 months.</label>
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    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_BondNotMeetingOriginalContractTermsMember" xlink:label="iboc_BondNotMeetingOriginalContractTermsMember" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_BondNotMeetingOriginalContractTermsMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Represents the portion of the bond where the underlying residential mortgage had been meeting the original contract terms for at least 24 months.</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_BondNotMeetingOriginalContractTermsMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Bond not meeting the original contract terms</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_ImpairedFinancingReceivableRecordedInvestmentFairValueDisclosure_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired Loans</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherAssetsAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Non-financial assets:</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_OtherRealEstateAndForeclosedAssetsInUse" xlink:label="iboc_OtherRealEstateAndForeclosedAssetsInUse" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_OtherRealEstateAndForeclosedAssetsInUse" xlink:to="iboc_OtherRealEstateAndForeclosedAssetsInUse_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_OtherRealEstateAndForeclosedAssetsInUse_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_OtherRealEstateAndForeclosedAssetsInUse_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other Real Estate and Foreclosed Assets in Use</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_OtherRealEstateAndForeclosedAssetsInUse_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other real estate owned</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FairValueAssumptionsAndMethodologyForAssetsAndLiabilitiesAbstract" xlink:label="us-gaap_FairValueAssumptionsAndMethodologyForAssetsAndLiabilitiesAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueAssumptionsAndMethodologyForAssetsAndLiabilitiesAbstract" xlink:to="us-gaap_FairValueAssumptionsAndMethodologyForAssetsAndLiabilitiesAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueAssumptionsAndMethodologyForAssetsAndLiabilitiesAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value Assumptions and Methodology for Assets and Liabilities [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueAssumptionsAndMethodologyForAssetsAndLiabilitiesAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Assumptions used in discounted cash flow model to determine fair value of investments classified within level 3</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_FairValueMeasurementsDiscountedCashFlowModelMinimumPerformancePeriodUnderOriginalTerms" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelMinimumPerformancePeriodUnderOriginalTerms" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_FairValueMeasurementsDiscountedCashFlowModelMinimumPerformancePeriodUnderOriginalTerms" xlink:to="iboc_FairValueMeasurementsDiscountedCashFlowModelMinimumPerformancePeriodUnderOriginalTerms_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelMinimumPerformancePeriodUnderOriginalTerms_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">The minimum period where the underlying residential mortgage loans must perform under original contract terms as a basis for certain discounted cash flow assumptions to be used.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelMinimumPerformancePeriodUnderOriginalTerms_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value Measurements Discounted Cash Flow Model Minimum Performance Period under Original Terms</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelMinimumPerformancePeriodUnderOriginalTerms_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Minimum period of residential mortgage loan performance under original contract terms</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsFuturePrincipalPrepaymentRatesLowEndOfRange" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsFuturePrincipalPrepaymentRatesLowEndOfRange" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsFuturePrincipalPrepaymentRatesLowEndOfRange" xlink:to="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsFuturePrincipalPrepaymentRatesLowEndOfRange_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsFuturePrincipalPrepaymentRatesLowEndOfRange_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">The low end of range of estimated future principal prepayment rate assumption used in the discounted cash flow model for investments classified within level 3 of the fair value hierarchy.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsFuturePrincipalPrepaymentRatesLowEndOfRange_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value Measurements, Discounted Cash Flow Model Assumptions Future Principal Prepayment Rates, Low End of Range</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsFuturePrincipalPrepaymentRatesLowEndOfRange_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Estimated future principal prepayment rate assumption, low end of range (as a percent)</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsDefaultRates" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsDefaultRates" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsDefaultRates" xlink:to="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsDefaultRates_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsDefaultRates_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Default rate assumption used in the discounted cash flow model for investments classified within level 3 of the fair value hierarchy.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsDefaultRates_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value, Measurements Discounted Cash Flow Model Assumptions Default Rates</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsDefaultRates_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Default rate assumptions (as a percent)</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsLossSeverityRatesForFirstYear" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsLossSeverityRatesForFirstYear" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsLossSeverityRatesForFirstYear" xlink:to="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsLossSeverityRatesForFirstYear_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsLossSeverityRatesForFirstYear_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loss severity rates assumption for the first year used in the discounted cash flow model for investments classified within level 3 of the fair value hierarchy.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsLossSeverityRatesForFirstYear_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value Measurements, Discounted Cash Flow Model Assumptions Loss Severity Rates for First Year</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsLossSeverityRatesForFirstYear_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loss severity rate assumptions, first year (as a percent)</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsDeclineInLossSeverityRatesForFollowingFifthYear" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsDeclineInLossSeverityRatesForFollowingFifthYear" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsDeclineInLossSeverityRatesForFollowingFifthYear" xlink:to="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsDeclineInLossSeverityRatesForFollowingFifthYear_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsDeclineInLossSeverityRatesForFollowingFifthYear_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">The decline in the loss severity rate assumptions for the following five years used in the discounted cash flow model for investments classified within level 3 of the fair value hierarchy.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsDeclineInLossSeverityRatesForFollowingFifthYear_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value Measurements Discounted Cash Flow Model Assumptions Decline in Loss Severity Rates for Following Fifth Year</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsDeclineInLossSeverityRatesForFollowingFifthYear_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Decrease in loss severity rates, following five years (as a percent)</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsLossSeverityRatesThereafter" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsLossSeverityRatesThereafter" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsLossSeverityRatesThereafter" xlink:to="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsLossSeverityRatesThereafter_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsLossSeverityRatesThereafter_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loss severity rates assumption for the remaining years used in the discounted cash flow model for investments classified within level 3 of the fair value hierarchy.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsLossSeverityRatesThereafter_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value Measurements, Discounted Cash Flow Model Assumptions Loss Severity Rates, Thereafter</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsLossSeverityRatesThereafter_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loss severity rate, thereafter (as a percent)</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsFuturePrincipalPrepaymentDiscountRate" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsFuturePrincipalPrepaymentDiscountRate" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsFuturePrincipalPrepaymentDiscountRate" xlink:to="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsFuturePrincipalPrepaymentDiscountRate_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsFuturePrincipalPrepaymentDiscountRate_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">The discount rate assumption of estimated future principal prepayment rate assumption used in the discounted cash flow model for investments classified within level 3 of the fair value hierarchy.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsFuturePrincipalPrepaymentDiscountRate_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value Measurements, Discounted Cash Flow Model Assumptions Future Principal Prepayment Discount Rate</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_FairValueMeasurementsDiscountedCashFlowModelAssumptionsFuturePrincipalPrepaymentDiscountRate_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Estimated future principal prepayment rate assumption, discount rate (as a percent)</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_ChangeInProvisionOfImpairedFinancingReceivableFairValueDisclosure" xlink:label="iboc_ChangeInProvisionOfImpairedFinancingReceivableFairValueDisclosure" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_ChangeInProvisionOfImpairedFinancingReceivableFairValueDisclosure" xlink:to="iboc_ChangeInProvisionOfImpairedFinancingReceivableFairValueDisclosure_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_ChangeInProvisionOfImpairedFinancingReceivableFairValueDisclosure_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">The estimated fair value of recorded investment related to change in provision for impaired financing receivables measured at fair value.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_ChangeInProvisionOfImpairedFinancingReceivableFairValueDisclosure_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Change in Provision of Impaired Financing Receivable, Fair Value Disclosure</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_ChangeInProvisionOfImpairedFinancingReceivableFairValueDisclosure_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Change in net provision, impaired loans</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_ChangeInProvisionOfOtherRealEstateAndForeclosedAssetsInUse" xlink:label="iboc_ChangeInProvisionOfOtherRealEstateAndForeclosedAssetsInUse" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_ChangeInProvisionOfOtherRealEstateAndForeclosedAssetsInUse" xlink:to="iboc_ChangeInProvisionOfOtherRealEstateAndForeclosedAssetsInUse_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_ChangeInProvisionOfOtherRealEstateAndForeclosedAssetsInUse_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Carrying amount as of the balance sheet date of change in Provision of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_ChangeInProvisionOfOtherRealEstateAndForeclosedAssetsInUse_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Change in Provision of Other Real Estate and Foreclosed Assets in Use</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_ChangeInProvisionOfOtherRealEstateAndForeclosedAssetsInUse_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Change in net provision, other real estate owned</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_AllowanceForLoanAndLeaseLossesPeriodIncreaseDecreaseLoansTransferredToOtherRealEstateOwned" xlink:label="iboc_AllowanceForLoanAndLeaseLossesPeriodIncreaseDecreaseLoansTransferredToOtherRealEstateOwned" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_AllowanceForLoanAndLeaseLossesPeriodIncreaseDecreaseLoansTransferredToOtherRealEstateOwned" xlink:to="iboc_AllowanceForLoanAndLeaseLossesPeriodIncreaseDecreaseLoansTransferredToOtherRealEstateOwned_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_AllowanceForLoanAndLeaseLossesPeriodIncreaseDecreaseLoansTransferredToOtherRealEstateOwned_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Amount of increase (decrease) of allowance reserve for credit losses in connection with loans transferred to other real estate owned.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_AllowanceForLoanAndLeaseLossesPeriodIncreaseDecreaseLoansTransferredToOtherRealEstateOwned_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Allowance for Loan and Lease Losses Period Increase (Decrease) Loans Transferred to Other Real Estate Owned</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_AllowanceForLoanAndLeaseLossesPeriodIncreaseDecreaseLoansTransferredToOtherRealEstateOwned_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Charges to allowance for probable loan losses in connection with other real estate owned</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_AllowanceForLoanLeaseLossesWriteOffsPriorToForeclosure" xlink:label="iboc_AllowanceForLoanLeaseLossesWriteOffsPriorToForeclosure" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_AllowanceForLoanLeaseLossesWriteOffsPriorToForeclosure" xlink:to="iboc_AllowanceForLoanLeaseLossesWriteOffsPriorToForeclosure_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_AllowanceForLoanLeaseLossesWriteOffsPriorToForeclosure_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Reflects the amount of charge-off related to a loan prior to foreclosure.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_AllowanceForLoanLeaseLossesWriteOffsPriorToForeclosure_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Allowance for Loan Lease Losses Write Offs Prior to Foreclosure</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_AllowanceForLoanLeaseLossesWriteOffsPriorToForeclosure_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Adjustment to fair value in connection with other real estate owned</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_ImpairedCommercialCollateralFinancingReceivableAppraisalsToDetermineFairValue" xlink:label="iboc_ImpairedCommercialCollateralFinancingReceivableAppraisalsToDetermineFairValue" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_ImpairedCommercialCollateralFinancingReceivableAppraisalsToDetermineFairValue" xlink:to="iboc_ImpairedCommercialCollateralFinancingReceivableAppraisalsToDetermineFairValue_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_ImpairedCommercialCollateralFinancingReceivableAppraisalsToDetermineFairValue_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Represents the impaired commercial collateral dependent financing receivables where the basis for fair value is an appraisal obtained in the last twelve months.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_ImpairedCommercialCollateralFinancingReceivableAppraisalsToDetermineFairValue_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired Commercial Collateral Financing Receivable Appraisals to Determine Fair Value</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_ImpairedCommercialCollateralFinancingReceivableAppraisalsToDetermineFairValue_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired commercial collateral dependent receivables appraisals to determine fair value within immediately preceding twelve months</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_ImpairedCollateralDependentCommercialLoansWithInternalEvaluationCompletedWithinLastTwelveMonths" xlink:label="iboc_ImpairedCollateralDependentCommercialLoansWithInternalEvaluationCompletedWithinLastTwelveMonths" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_ImpairedCollateralDependentCommercialLoansWithInternalEvaluationCompletedWithinLastTwelveMonths" xlink:to="iboc_ImpairedCollateralDependentCommercialLoansWithInternalEvaluationCompletedWithinLastTwelveMonths_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_ImpairedCollateralDependentCommercialLoansWithInternalEvaluationCompletedWithinLastTwelveMonths_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">The impaired collateral dependent commercial loans where an internal evaluation has been done in the last twelve months.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_ImpairedCollateralDependentCommercialLoansWithInternalEvaluationCompletedWithinLastTwelveMonths_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired collateral dependent commercial loans with internal evaluation completed within last twelve months</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract" xlink:label="us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract" xlink:to="us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loans and Leases Receivable, Net Amount [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loans</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LoansReceivableWithFixedRatesOfInterest1" xlink:label="us-gaap_LoansReceivableWithFixedRatesOfInterest1" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LoansReceivableWithFixedRatesOfInterest1" xlink:to="us-gaap_LoansReceivableWithFixedRatesOfInterest1_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LoansReceivableWithFixedRatesOfInterest1_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loans Receivable with Fixed Rates of Interest</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LoansReceivableWithFixedRatesOfInterest1_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Carrying amount of fixed rate performing loans</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_LoansReceivableWithFixedRateOfInterestFairValueDisclosure" xlink:label="iboc_LoansReceivableWithFixedRateOfInterestFairValueDisclosure" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_LoansReceivableWithFixedRateOfInterestFairValueDisclosure" xlink:to="iboc_LoansReceivableWithFixedRateOfInterestFairValueDisclosure_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_LoansReceivableWithFixedRateOfInterestFairValueDisclosure_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Represents the portion of fixed rate performing loans valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Fixed rate loan represents loans charging borrowers fixed rates of interest.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_LoansReceivableWithFixedRateOfInterestFairValueDisclosure_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loans Receivable with Fixed Rate of Interest Fair Value, Disclosure</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_LoansReceivableWithFixedRateOfInterestFairValueDisclosure_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Estimated fair value of fixed rate performing loans</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_TimeDepositsFairValueDisclosure" xlink:label="iboc_TimeDepositsFairValueDisclosure" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_TimeDepositsFairValueDisclosure" xlink:to="iboc_TimeDepositsFairValueDisclosure_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_TimeDepositsFairValueDisclosure_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Represents the portion of time deposits valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Time deposits include certificates of deposits, individual retirement accounts and open accounts.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_TimeDepositsFairValueDisclosure_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Time Deposits Fair Value, Disclosure</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_TimeDepositsFairValueDisclosure_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Estimated fair value of time deposits</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseAbstract" xlink:label="us-gaap_FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseAbstract" xlink:to="us-gaap_FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Securities Sold Under Repurchase Agreements</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_SecuritiesSoldUnderLongTermAgreementsToRepurchase" xlink:label="iboc_SecuritiesSoldUnderLongTermAgreementsToRepurchase" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_SecuritiesSoldUnderLongTermAgreementsToRepurchase" xlink:to="iboc_SecuritiesSoldUnderLongTermAgreementsToRepurchase_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_SecuritiesSoldUnderLongTermAgreementsToRepurchase_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">The carrying value as of the balance sheet date of securities that an institution sells and agrees to repurchase under a long term agreement (the identical or substantially the same securities) as a seller-borrower at a specified date for a specified price, also known as a repurchase agreement.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_SecuritiesSoldUnderLongTermAgreementsToRepurchase_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Securities Sold under Long Term Agreements to Repurchase</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_SecuritiesSoldUnderLongTermAgreementsToRepurchase_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Carrying amount of long-term repurchase agreements</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseFairValueDisclosure" xlink:label="us-gaap_SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseFairValueDisclosure" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseFairValueDisclosure" xlink:to="us-gaap_SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseFairValueDisclosure_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseFairValueDisclosure_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Securities Loaned or Sold under Agreements to Repurchase, Fair Value Disclosure</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseFairValueDisclosure_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Estimated fair value of long-term repurchase agreements</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LoansAndLeasesReceivableNetOfDeferredIncomeAbstract" xlink:label="us-gaap_LoansAndLeasesReceivableNetOfDeferredIncomeAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LoansAndLeasesReceivableNetOfDeferredIncomeAbstract" xlink:to="us-gaap_LoansAndLeasesReceivableNetOfDeferredIncomeAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LoansAndLeasesReceivableNetOfDeferredIncomeAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Summary of net loans</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable" xlink:label="us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable" xlink:to="us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Schedule of Accounts, Notes, Loans and Financing Receivable [Table]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis" xlink:label="us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis" xlink:to="us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Receivable Type [Axis]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ReceivableTypeDomain" xlink:label="us-gaap_ReceivableTypeDomain" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ReceivableTypeDomain" xlink:to="us-gaap_ReceivableTypeDomain_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ReceivableTypeDomain_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Receivable Type [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ReceivableTypeDomain_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Receivable [Domain]</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_LoansReceivableCommercialFinancialAndAgriculturalMember" xlink:label="iboc_LoansReceivableCommercialFinancialAndAgriculturalMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_LoansReceivableCommercialFinancialAndAgriculturalMember" xlink:to="iboc_LoansReceivableCommercialFinancialAndAgriculturalMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_LoansReceivableCommercialFinancialAndAgriculturalMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">A loan, whether secured or unsecured, to a company for purposes such as seasonal working capital needs, inventory financing, equipment purchases, agricultural purposes and acquisitions.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_LoansReceivableCommercialFinancialAndAgriculturalMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loans Receivable Commercial Financial And Agricultural [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_LoansReceivableCommercialFinancialAndAgriculturalMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Commercial, financial and agricultural</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ResidentialMortgageMember" xlink:label="us-gaap_ResidentialMortgageMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ResidentialMortgageMember" xlink:to="us-gaap_ResidentialMortgageMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ResidentialMortgageMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Residential Mortgage [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ResidentialMortgageMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Real estate - mortgage</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember" xlink:label="iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember" xlink:to="iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Class of financing receivables related to commercial real estate that is for other construction and land development purposes.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Commercial Real Estate Other Construction And Land Development Receivable [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Commercial Real Estate: Other Construction and Land Development</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ConsumerLoanMember" xlink:label="us-gaap_ConsumerLoanMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ConsumerLoanMember" xlink:to="us-gaap_ConsumerLoanMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ConsumerLoanMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Consumer Loan [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ConsumerLoanMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Consumer</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_ForeignReceivablesMember" xlink:label="iboc_ForeignReceivablesMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_ForeignReceivablesMember" xlink:to="iboc_ForeignReceivablesMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_ForeignReceivablesMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Class of financing receivables related to a location outside of the entity's country of domicile.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_ForeignReceivablesMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Foreign Receivables [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_ForeignReceivablesMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Foreign</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems" xlink:label="us-gaap_AccountsNotesAndLoansReceivableLineItems" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AccountsNotesAndLoansReceivableLineItems" xlink:to="us-gaap_AccountsNotesAndLoansReceivableLineItems_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AccountsNotesAndLoansReceivableLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Accounts, Notes, Loans and Financing Receivable [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AccountsNotesAndLoansReceivableLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Summary of loans, by loan type</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable" xlink:label="us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable" xlink:to="us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Schedule of Financing Receivable, Allowance for Credit Losses [Table]</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_ReceivablesFromDomesticOperationsMember" xlink:label="iboc_ReceivablesFromDomesticOperationsMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_ReceivablesFromDomesticOperationsMember" xlink:to="iboc_ReceivablesFromDomesticOperationsMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_ReceivablesFromDomesticOperationsMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Class of financing receivables related to the entity's country of domicile.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_ReceivablesFromDomesticOperationsMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Receivables From Domestic Operations [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_ReceivablesFromDomesticOperationsMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Receivables from Domestic Operations [Member]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CommercialLoanMember" xlink:label="us-gaap_CommercialLoanMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommercialLoanMember" xlink:to="us-gaap_CommercialLoanMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommercialLoanMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Commercial Loan [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommercialLoanMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Commercial</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember" xlink:label="iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember" xlink:to="iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Class of financing receivables related to commercial real estate that is for farmland and commercial purposes.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Commercial Real Estate Farmland And Commercial Receivable [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Commercial Real Estate: Farmland &amp; Commercial</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_CommercialRealEstateMultifamilyReceivableMember" xlink:label="iboc_CommercialRealEstateMultifamilyReceivableMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_CommercialRealEstateMultifamilyReceivableMember" xlink:to="iboc_CommercialRealEstateMultifamilyReceivableMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_CommercialRealEstateMultifamilyReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Class of financing receivables related to commercial real estate that is for multifamily purposes.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_CommercialRealEstateMultifamilyReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Commercial Real Estate Multifamily Receivable [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_CommercialRealEstateMultifamilyReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Commercial Real Estate: Multifamily</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_ResidentialFirstMortgageFinancingReceivableMember" xlink:label="iboc_ResidentialFirstMortgageFinancingReceivableMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_ResidentialFirstMortgageFinancingReceivableMember" xlink:to="iboc_ResidentialFirstMortgageFinancingReceivableMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_ResidentialFirstMortgageFinancingReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Class of financing receivables related to residential receivables secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_ResidentialFirstMortgageFinancingReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Residential First Mortgage Financing Receivable [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_ResidentialFirstMortgageFinancingReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Residential First Lien</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_ResidentialSecondMortgageFinancingReceivableMember" xlink:label="iboc_ResidentialSecondMortgageFinancingReceivableMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_ResidentialSecondMortgageFinancingReceivableMember" xlink:to="iboc_ResidentialSecondMortgageFinancingReceivableMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_ResidentialSecondMortgageFinancingReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Class of financing receivables related to residential receivables secured by real property that has a second (lower or subordinate) lien on such property in the event of default by the borrower.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_ResidentialSecondMortgageFinancingReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Residential Second Mortgage Financing Receivable [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_ResidentialSecondMortgageFinancingReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Residential Junior Lien</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems" xlink:label="us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems" xlink:to="us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivable, Allowance for Credit Losses [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loan loss allowances</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loan loss allowances, impaired financing receivable, evaluated individually or collectively</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AllowanceForLoanAndLeaseLossesRollForward" xlink:label="us-gaap_AllowanceForLoanAndLeaseLossesRollForward" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AllowanceForLoanAndLeaseLossesRollForward" xlink:to="us-gaap_AllowanceForLoanAndLeaseLossesRollForward_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AllowanceForLoanAndLeaseLossesRollForward_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Allowance for Loan and Lease Losses [Roll Forward]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AllowanceForLoanAndLeaseLossesRollForward_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Allowance for probable loan losses</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs" xlink:label="us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs" xlink:to="us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Allowance for Loan and Lease Losses, Write-offs</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Losses charged to allowance</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AllowanceForLoanAndLeaseLossRecoveryOfBadDebts" xlink:label="us-gaap_AllowanceForLoanAndLeaseLossRecoveryOfBadDebts" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AllowanceForLoanAndLeaseLossRecoveryOfBadDebts" xlink:to="us-gaap_AllowanceForLoanAndLeaseLossRecoveryOfBadDebts_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AllowanceForLoanAndLeaseLossRecoveryOfBadDebts_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Allowance for Loan and Lease Loss, Recovery of Bad Debts</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AllowanceForLoanAndLeaseLossRecoveryOfBadDebts_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Recoveries credited to allowance</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AllowanceForLoanAndLeaseLossesWriteoffsNet" xlink:label="us-gaap_AllowanceForLoanAndLeaseLossesWriteoffsNet" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AllowanceForLoanAndLeaseLossesWriteoffsNet" xlink:to="us-gaap_AllowanceForLoanAndLeaseLossesWriteoffsNet_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AllowanceForLoanAndLeaseLossesWriteoffsNet_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Allowance for Loan and Lease Losses Write-offs, Net</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_AllowanceForLoanAndLeaseLossesWriteoffsNet_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Net (losses) recoveries charged to allowance</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment" xlink:label="us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment" xlink:to="us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivable, Individually Evaluated for Impairment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loans Individually Evaluated for Impairment, Recorded Investment</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1" xlink:label="us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1" xlink:to="us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loans Individually Evaluated for Impairment, Allowance</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment" xlink:label="us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment" xlink:to="us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivable, Collectively Evaluated for Impairment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loans Collectively Evaluated for Impairment, Recorded Investment</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment" xlink:label="us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment" xlink:to="us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loans Collectively Evaluated for Impairment, Allowance</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfFinancingReceivablesPastDueTable" xlink:label="us-gaap_ScheduleOfFinancingReceivablesPastDueTable" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfFinancingReceivablesPastDueTable" xlink:to="us-gaap_ScheduleOfFinancingReceivablesPastDueTable_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfFinancingReceivablesPastDueTable_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Schedule of Financing Receivables Past Due [Table]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems" xlink:to="us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivable, Recorded Investment, Past Due [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loan loss allowances, financing receivable past due</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableRecordedInvestmentNonaccrualStatus" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentNonaccrualStatus" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivableRecordedInvestmentNonaccrualStatus" xlink:to="us-gaap_FinancingReceivableRecordedInvestmentNonaccrualStatus_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentNonaccrualStatus_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivable, Recorded Investment, Nonaccrual Status</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentNonaccrualStatus_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Non-accrual loans, total</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfImpairedFinancingReceivableTable" xlink:label="us-gaap_ScheduleOfImpairedFinancingReceivableTable" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfImpairedFinancingReceivableTable" xlink:to="us-gaap_ScheduleOfImpairedFinancingReceivableTable_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfImpairedFinancingReceivableTable_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Schedule of Impaired Financing Receivable [Table]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis" xlink:to="us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Class of Financing Receivable [Axis]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain" xlink:to="us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivable Recorded Investment Class Of Financing Receivable [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Class of Financing Receivable [Domain]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_UnallocatedFinancingReceivablesMember" xlink:label="us-gaap_UnallocatedFinancingReceivablesMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_UnallocatedFinancingReceivablesMember" xlink:to="us-gaap_UnallocatedFinancingReceivablesMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_UnallocatedFinancingReceivablesMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Unallocated Financing Receivables [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_UnallocatedFinancingReceivablesMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Class of Financing Receivable</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableImpairedLineItems" xlink:label="us-gaap_FinancingReceivableImpairedLineItems" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivableImpairedLineItems" xlink:to="us-gaap_FinancingReceivableImpairedLineItems_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableImpairedLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivable, Impaired [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivableImpairedLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loan loss allowances, impaired financing receivable</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ImpairedFinancingReceivableRecordedInvestmentAbstract" xlink:label="us-gaap_ImpairedFinancingReceivableRecordedInvestmentAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ImpairedFinancingReceivableRecordedInvestmentAbstract" xlink:to="us-gaap_ImpairedFinancingReceivableRecordedInvestmentAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ImpairedFinancingReceivableRecordedInvestmentAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired Financing Receivable, Recorded Investment [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ImpairedFinancingReceivableRecordedInvestmentAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Recorded investment:</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment" xlink:label="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment" xlink:to="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired Financing Receivable, with Related Allowance, Recorded Investment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total impaired loans with related allowance</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment" xlink:label="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment" xlink:to="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired Financing Receivable, with No Related Allowance, Recorded Investment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total impaired loans with no related allowance</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalanceAbstract" xlink:label="us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalanceAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalanceAbstract" xlink:to="us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalanceAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalanceAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired Financing Receivable, Unpaid Principal Balance [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalanceAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Unpaid principal balance:</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance" xlink:label="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance" xlink:to="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total impaired loans with an allowance recorded</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance" xlink:label="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance" xlink:to="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total impaired loans with no related allowance recorded</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ImpairedFinancingReceivableRelatedAllowance" xlink:label="us-gaap_ImpairedFinancingReceivableRelatedAllowance" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ImpairedFinancingReceivableRelatedAllowance" xlink:to="us-gaap_ImpairedFinancingReceivableRelatedAllowance_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ImpairedFinancingReceivableRelatedAllowance_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired Financing Receivable, Related Allowance</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ImpairedFinancingReceivableRelatedAllowance_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Related Allowance</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ImpairedFinancingReceivableAverageRecordedInvestmentAbstract" xlink:label="us-gaap_ImpairedFinancingReceivableAverageRecordedInvestmentAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ImpairedFinancingReceivableAverageRecordedInvestmentAbstract" xlink:to="us-gaap_ImpairedFinancingReceivableAverageRecordedInvestmentAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ImpairedFinancingReceivableAverageRecordedInvestmentAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired Financing Receivable, Average Recorded Investment [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ImpairedFinancingReceivableAverageRecordedInvestmentAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Average recorded investment:</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment" xlink:label="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment" xlink:to="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired Financing Receivable, with Related Allowance, Average Recorded Investment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total impaired loans with an allowance recorded</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment" xlink:label="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment" xlink:to="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total impaired loans with no related allowance recorded</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ImpairedFinancingReceivableInterestIncomeAccrualMethodAbstract" xlink:label="us-gaap_ImpairedFinancingReceivableInterestIncomeAccrualMethodAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ImpairedFinancingReceivableInterestIncomeAccrualMethodAbstract" xlink:to="us-gaap_ImpairedFinancingReceivableInterestIncomeAccrualMethodAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ImpairedFinancingReceivableInterestIncomeAccrualMethodAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired Financing Receivable, Interest Income, Accrual Method [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ImpairedFinancingReceivableInterestIncomeAccrualMethodAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest Recognized</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod" xlink:label="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod" xlink:to="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total impaired loans with an allowance recorded</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod" xlink:label="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod" xlink:to="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total impaired loans with no related allowance recorded</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableModificationsRecordedInvestment" xlink:label="us-gaap_FinancingReceivableModificationsRecordedInvestment" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivableModificationsRecordedInvestment" xlink:to="us-gaap_FinancingReceivableModificationsRecordedInvestment_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableModificationsRecordedInvestment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total troubled debt restructuring</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_FinancingReceivableModificationsRecordedInvestment_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total trouble debt restructuring</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ThresholdPeriodPastDueForWriteoffOfFinancingReceivable" xlink:label="us-gaap_ThresholdPeriodPastDueForWriteoffOfFinancingReceivable" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ThresholdPeriodPastDueForWriteoffOfFinancingReceivable" xlink:to="us-gaap_ThresholdPeriodPastDueForWriteoffOfFinancingReceivable_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ThresholdPeriodPastDueForWriteoffOfFinancingReceivable_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Threshold Period Past Due for Write-off of Financing Receivable</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ThresholdPeriodPastDueForWriteoffOfFinancingReceivable_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Period of charge off for past due unsecured commercial loans</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivablesPeriodPastDueAxis" xlink:label="us-gaap_FinancingReceivablesPeriodPastDueAxis" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivablesPeriodPastDueAxis" xlink:to="us-gaap_FinancingReceivablesPeriodPastDueAxis_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivablesPeriodPastDueAxis_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivables, Period Past Due [Axis]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain" xlink:label="us-gaap_FinancingReceivablesPeriodPastDueDomain" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivablesPeriodPastDueDomain" xlink:to="us-gaap_FinancingReceivablesPeriodPastDueDomain_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivablesPeriodPastDueDomain_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivables Period Past Due [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivablesPeriodPastDueDomain_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivables, Period Past Due [Domain]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivables30To59DaysPastDueMember" xlink:label="us-gaap_FinancingReceivables30To59DaysPastDueMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivables30To59DaysPastDueMember" xlink:to="us-gaap_FinancingReceivables30To59DaysPastDueMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivables30To59DaysPastDueMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivables30 To59 Days Past Due [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivables30To59DaysPastDueMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">30 to 59 Days</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivables60To89DaysPastDueMember" xlink:label="us-gaap_FinancingReceivables60To89DaysPastDueMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivables60To89DaysPastDueMember" xlink:to="us-gaap_FinancingReceivables60To89DaysPastDueMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivables60To89DaysPastDueMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivables60 To89 Days Past Due [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivables60To89DaysPastDueMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">60 to 89 Days</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember" xlink:label="us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember" xlink:to="us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivables Equal To Greater Than90 Days Past Due [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">90 Days or Greater</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableRecordedInvestmentAgingAbstract" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentAgingAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivableRecordedInvestmentAgingAbstract" xlink:to="us-gaap_FinancingReceivableRecordedInvestmentAgingAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentAgingAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivable, Recorded Investment, Aging [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentAgingAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing receivable recorded investment</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableRecordedInvestmentPastDue" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentPastDue" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivableRecordedInvestmentPastDue" xlink:to="us-gaap_FinancingReceivableRecordedInvestmentPastDue_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentPastDue_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivable, Recorded Investment, Past Due</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentPastDue_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Past due</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing" xlink:label="us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing" xlink:to="us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Past due 90 days or Greater and Still Accruing</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableRecordedInvestmentCurrent" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentCurrent" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivableRecordedInvestmentCurrent" xlink:to="us-gaap_FinancingReceivableRecordedInvestmentCurrent_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentCurrent_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivable, Recorded Investment, Current</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentCurrent_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loans, current</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable" xlink:label="us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable" xlink:to="us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Schedule of Financing Receivable, Recorded Investment, Credit Quality Indicator [Table]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InternalCreditAssessmentAxis" xlink:label="us-gaap_InternalCreditAssessmentAxis" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InternalCreditAssessmentAxis" xlink:to="us-gaap_InternalCreditAssessmentAxis_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InternalCreditAssessmentAxis_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Internal Credit Assessment [Axis]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_InternalCreditAssessmentDomain" xlink:label="us-gaap_InternalCreditAssessmentDomain" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InternalCreditAssessmentDomain" xlink:to="us-gaap_InternalCreditAssessmentDomain_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InternalCreditAssessmentDomain_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Internal Credit Assessment [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InternalCreditAssessmentDomain_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Internal Credit Assessment [Domain]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PassMember" xlink:label="us-gaap_PassMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PassMember" xlink:to="us-gaap_PassMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PassMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Pass [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PassMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Pass</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_SpecialMentionMember" xlink:label="us-gaap_SpecialMentionMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SpecialMentionMember" xlink:to="us-gaap_SpecialMentionMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SpecialMentionMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Special Mention [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SpecialMentionMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Special Review</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_SpecialPassMember" xlink:label="iboc_SpecialPassMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_SpecialPassMember" xlink:to="iboc_SpecialPassMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_SpecialPassMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">A category of financing receivables considered to have weaknesses which represent a greater degree of risk, warranting "extra attention".</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_SpecialPassMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Special Pass [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_SpecialPassMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Watch List - Pass</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_SubstandardMember" xlink:label="us-gaap_SubstandardMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SubstandardMember" xlink:to="us-gaap_SubstandardMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SubstandardMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Substandard [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SubstandardMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Watch List - Substandard</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NonperformingFinancingReceivableMember" xlink:label="us-gaap_NonperformingFinancingReceivableMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NonperformingFinancingReceivableMember" xlink:to="us-gaap_NonperformingFinancingReceivableMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NonperformingFinancingReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Nonperforming Financing Receivable [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NonperformingFinancingReceivableMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Watch - List Impaired</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FinancingReceivableRecordedInvestmentLineItems" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentLineItems" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FinancingReceivableRecordedInvestmentLineItems" xlink:to="us-gaap_FinancingReceivableRecordedInvestmentLineItems_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Financing Receivable, Recorded Investment [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinancingReceivableRecordedInvestmentLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Loan portfolio by credit quality indicator</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:to="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="us-gaap_AwardTypeAxis" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AwardTypeAxis" xlink:to="us-gaap_AwardTypeAxis_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AwardTypeAxis_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Award Type [Axis]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Share Based Compensation Arrangements By Share Based Payment Award Award Type And Plan Name [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Equity Award [Domain]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="us-gaap_EmployeeStockOptionMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EmployeeStockOptionMember" xlink:to="us-gaap_EmployeeStockOptionMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EmployeeStockOptionMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Employee Stock Option [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EmployeeStockOptionMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Stock options under 2012 Plan</label>
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_IncentiveStockOptionsTo10PercentShareholdersMember" xlink:to="iboc_IncentiveStockOptionsTo10PercentShareholdersMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_IncentiveStockOptionsTo10PercentShareholdersMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Common stock awarded by the entity to 10% shareholders as a form of an incentive compensation under the incentive stock option plan.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_IncentiveStockOptionsTo10PercentShareholdersMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Incentive Stock Options To10 Percent Shareholders [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_IncentiveStockOptionsTo10PercentShareholdersMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Incentive stock options granted to 10% shareholders</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Share-based Compensation Arrangement by Share-based Payment Award [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Stock option details</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Shares available for future grants</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod" xlink:to="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Maximum exercisable period for options granted</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Stock option activity</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Options outstanding at the end of the period (in shares)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Options outstanding at the beginning of the period (in shares)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Plus: Options granted (in shares)</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsReductionsFromOutstandingAbstract" xlink:label="iboc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsReductionsFromOutstandingAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsReductionsFromOutstandingAbstract" xlink:to="iboc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsReductionsFromOutstandingAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsReductionsFromOutstandingAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Share Based Compensation Arrangement by Share Based Payment Award, Options Reductions from Outstanding [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsReductionsFromOutstandingAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Less:</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:to="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Options exercised (in shares)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Options forfeited (in shares)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Options fully vested and exercisable at the end of the period (in shares)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Stock Options, Weighted Average Exercise Price</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Options outstanding at the end, weighted average exercise price (in dollars per share)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Options outstanding at the beginning, weighted average exercise price (in dollars per share)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Plus: Options granted, weighted average exercise price (in dollars per share)</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsReductionsFromOutstandingWeightedAverageExercisePriceAbstract" xlink:label="iboc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsReductionsFromOutstandingWeightedAverageExercisePriceAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsReductionsFromOutstandingWeightedAverageExercisePriceAbstract" xlink:to="iboc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsReductionsFromOutstandingWeightedAverageExercisePriceAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsReductionsFromOutstandingWeightedAverageExercisePriceAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Share Based Compensation Arrangement by Share Based Payment Award, Options Reductions from Outstanding Weighted Average Exercise Price [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsReductionsFromOutstandingWeightedAverageExercisePriceAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Less:</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AvailableForSaleSecuritiesEquitySecurities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Available-for-sale Securities, Equity Securities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AvailableForSaleSecuritiesEquitySecurities_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Equity securities, Estimated Fair Value</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_AvailableForSaleSecuritiesPledgedAsCollateralAmortizedCost_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">The amortized cost of available-for-sale securities that serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party.</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_AvailableForSaleSecuritiesPledgedAsCollateralAmortizedCost_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Amortized cost of available for sale investment securities pledged</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AvailableForSaleSecuritiesPledgedAsCollateral_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Available-for-sale Securities Pledged as Collateral</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AvailableForSaleSecuritiesPledgedAsCollateral_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair value of available for sale investment securities pledged</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromSaleOfMortgageBackedSecuritiesMBSCategorizedAsAvailableForSale_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Proceeds from Sale of Mortgage Backed Securities (MBS) categorized as Available-for-sale</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecuritiesGrossRealizedGains" xlink:label="us-gaap_AvailableForSaleSecuritiesGrossRealizedGains" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AvailableForSaleSecuritiesGrossRealizedGains" xlink:to="us-gaap_AvailableForSaleSecuritiesGrossRealizedGains_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AvailableForSaleSecuritiesGrossRealizedGains_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Available-for-sale Securities, Gross Realized Gains</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AvailableForSaleSecuritiesGrossRealizedGains_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Gross gains realized on sales</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses" xlink:label="us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses" xlink:to="us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Available-for-sale Securities, Gross Realized Losses</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Gross losses realized on sales</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract" xlink:label="us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract" xlink:to="us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Available for sale:</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair value, less than 12 months</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Unrealized losses, less than 12 Months</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair value, 12 months or more</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Unrealized losses, 12 Months or More</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair value, total</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Credit-related impairment charges on investments recognized in earnings</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsRollForward" xlink:label="us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsRollForward" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsRollForward_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsRollForward_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Reconciliation of credit-related impairment charges on investments recognized in earnings</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld" xlink:label="us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld" xlink:to="us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other than Temporary Impairment, Credit Losses Recognized in Earnings, Credit Losses on Debt Securities Held</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Balance at the end</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLosses_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, Additional Credit Losses</label>
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    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLossesAfterTax" xlink:label="iboc_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLossesAfterTax" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLossesAfterTax" xlink:to="iboc_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLossesAfterTax_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLossesAfterTax_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">This item represents the after tax effect of an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which a previous OTTI was recognized and the investor does not intend to sell the debt security and it is not more likely than not that the investor will be required to sell the debt security before recovery of its amortized cost basis.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLossesAfterTax_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, Additional Credit Losses after Tax</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLossesAfterTax_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Impairment charges, after tax, recognized during period</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="us-gaap_DebtInstrumentLineItems" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Debt Instrument [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentLineItems_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Junior subordinated deferrable interest debentures, major types of business trusts</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AdvancesFromFederalHomeLoanBanksAbstract" xlink:label="us-gaap_AdvancesFromFederalHomeLoanBanksAbstract" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_PercentageOfAdvancesFromFederalHomeLoanBanksIncreaseDecrease_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Represents the percentage change in other borrowed funds. Borrowed funds primarily consist of short and long term borrowings from the Federal Home Loan Bank.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_PercentageOfAdvancesFromFederalHomeLoanBanksIncreaseDecrease_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Percentage of Advances from Federal Home Loan Banks Increase (Decrease)</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="us-gaap_DebtInstrumentAxis" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_TrustElevenMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Trust XI</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_TrustElevenMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Trust Eleven [Member]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_DebtInstrumentsRedemptionPriceDiscount_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Represents the percentage of discount from redemption price of debt.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_DebtInstrumentsRedemptionPriceDiscount_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Debt Instruments Redemption Price Discount</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_DebtInstrumentsRedemptionPriceDiscount_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Redemption price discount (as a percent)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_RepaymentsOfDebt" xlink:label="us-gaap_RepaymentsOfDebt" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RepaymentsOfDebt" xlink:to="us-gaap_RepaymentsOfDebt_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RepaymentsOfDebt_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Repayments of Debt</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RepaymentsOfDebt_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Retirement of capital securities</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_MaximumNumberOfConsecutiveQuarterlyPeriodsAvailableForDeferralOfPaymentOfInterest" xlink:label="iboc_MaximumNumberOfConsecutiveQuarterlyPeriodsAvailableForDeferralOfPaymentOfInterest" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_MaximumNumberOfConsecutiveQuarterlyPeriodsAvailableForDeferralOfPaymentOfInterest" xlink:to="iboc_MaximumNumberOfConsecutiveQuarterlyPeriodsAvailableForDeferralOfPaymentOfInterest_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_MaximumNumberOfConsecutiveQuarterlyPeriodsAvailableForDeferralOfPaymentOfInterest_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Represents the maximum number of consecutive quarterly periods available to the entity for deferring the payment of interest on Trusts VI, VII, VIII, IX, X, XI and XII.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_MaximumNumberOfConsecutiveQuarterlyPeriodsAvailableForDeferralOfPaymentOfInterest_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Maximum Number of Consecutive Quarterly Periods Available-for-Deferral of Payment of Interest</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_MaximumNumberOfConsecutiveQuarterlyPeriodsAvailableForDeferralOfPaymentOfInterest_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Maximum number of consecutive quarterly period available for deferral of interest payment on Trusts VI, VII, VIII, IX, X, XI and XII</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_MaximumPercentageOfCapitalSecuritiesIssuedByTrustQualifyingAsTierOneCapital" xlink:label="iboc_MaximumPercentageOfCapitalSecuritiesIssuedByTrustQualifyingAsTierOneCapital" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_MaximumPercentageOfCapitalSecuritiesIssuedByTrustQualifyingAsTierOneCapital" xlink:to="iboc_MaximumPercentageOfCapitalSecuritiesIssuedByTrustQualifyingAsTierOneCapital_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_MaximumPercentageOfCapitalSecuritiesIssuedByTrustQualifyingAsTierOneCapital_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Represents the maximum percentage of capital securities issued by the trust qualifying as Tier I capital on an aggregate basis.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_MaximumPercentageOfCapitalSecuritiesIssuedByTrustQualifyingAsTierOneCapital_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Maximum Percentage of Capital Securities Issued by Trust Qualifying as Tier One Capital</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_MaximumPercentageOfCapitalSecuritiesIssuedByTrustQualifyingAsTierOneCapital_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Percentage of capital securities issued by trust qualifying as Tier I capital, maximum</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_MinimumPercentageOfCapitalSecuritiesIssuedByTrustQualifyingAsTierTwoCapital" xlink:label="iboc_MinimumPercentageOfCapitalSecuritiesIssuedByTrustQualifyingAsTierTwoCapital" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_MinimumPercentageOfCapitalSecuritiesIssuedByTrustQualifyingAsTierTwoCapital" xlink:to="iboc_MinimumPercentageOfCapitalSecuritiesIssuedByTrustQualifyingAsTierTwoCapital_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_MinimumPercentageOfCapitalSecuritiesIssuedByTrustQualifyingAsTierTwoCapital_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Represents the minimum percentage of capital securities issued by the trust qualifying as Tier II capital on an aggregate basis.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_MinimumPercentageOfCapitalSecuritiesIssuedByTrustQualifyingAsTierTwoCapital_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Minimum Percentage of Capital Securities Issued by Trust Qualifying as Tier Two Capital</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_MinimumPercentageOfCapitalSecuritiesIssuedByTrustQualifyingAsTierTwoCapital_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Percentage of capital securities issued by trust qualifying as Tier II capital, minimum</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_CapitalSecuritiesIssuedByTrustQualifyingAsTierOneCapital" xlink:label="iboc_CapitalSecuritiesIssuedByTrustQualifyingAsTierOneCapital" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_CapitalSecuritiesIssuedByTrustQualifyingAsTierOneCapital" xlink:to="iboc_CapitalSecuritiesIssuedByTrustQualifyingAsTierOneCapital_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_CapitalSecuritiesIssuedByTrustQualifyingAsTierOneCapital_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Represents capital securities issued by trust that is qualified as Tier I capital as on the reporting date.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_CapitalSecuritiesIssuedByTrustQualifyingAsTierOneCapital_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Capital Securities Issued by Trust, Qualifying as Tier One Capital</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_CapitalSecuritiesIssuedByTrustQualifyingAsTierOneCapital_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Capital securities issued by the trust, qualifying as Tier I capital</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_TrustSixMember" xlink:label="iboc_TrustSixMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_TrustSixMember" xlink:to="iboc_TrustSixMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_TrustSixMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Trust VI</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_TrustSixMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Trust Six [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_TrustSixMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Trust VI</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_TrustEightMember" xlink:label="iboc_TrustEightMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_TrustEightMember" xlink:to="iboc_TrustEightMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_TrustEightMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Trust VIII</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_TrustEightMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Trust Eight [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_TrustEightMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Trust VIII</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_TrustNineMember" xlink:label="iboc_TrustNineMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_TrustNineMember" xlink:to="iboc_TrustNineMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_TrustNineMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Trust IX</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_TrustNineMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Trust Nine [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_TrustNineMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Trust IX</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_TrustTwelveMember" xlink:label="iboc_TrustTwelveMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_TrustTwelveMember" xlink:to="iboc_TrustTwelveMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_TrustTwelveMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Trust XII</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_TrustTwelveMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Trust Twelve [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_TrustTwelveMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Trust XII</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DebtInstrumentInterestRateDuringPeriod" xlink:label="us-gaap_DebtInstrumentInterestRateDuringPeriod" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentInterestRateDuringPeriod" xlink:to="us-gaap_DebtInstrumentInterestRateDuringPeriod_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentInterestRateDuringPeriod_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Debt Instrument, Interest Rate During Period</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentInterestRateDuringPeriod_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest rate (as a percent)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DebtInstrumentInterestRateTerms" xlink:label="us-gaap_DebtInstrumentInterestRateTerms" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentInterestRateTerms" xlink:to="us-gaap_DebtInstrumentInterestRateTerms_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentInterestRateTerms_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Debt Instrument, Interest Rate Terms</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentInterestRateTerms_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Interest rate index</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:label="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:to="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Debt Instrument, Basis Spread on Variable Rate</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Spread on interest rate index (as a percent)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PreferredStockSharesOutstanding" xlink:label="us-gaap_PreferredStockSharesOutstanding" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockSharesOutstanding" xlink:to="us-gaap_PreferredStockSharesOutstanding_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Preferred Stock, Shares Outstanding</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Series A cumulative perpetual preferred shares, outstanding</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:to="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Class of Warrant or Right, Number of Securities Called by Warrants or Rights</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Warrants to purchase entity's common stock (in shares)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:to="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Class of Warrant or Right, Exercise Price of Warrants or Rights</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Warrants, exercise price (in dollars per share)</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_AggregateCommonStockInvestmentAsPercentageOfSeniorPreferredStockInvestmentOnExerciseOfWarrants" xlink:label="iboc_AggregateCommonStockInvestmentAsPercentageOfSeniorPreferredStockInvestmentOnExerciseOfWarrants" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_AggregateCommonStockInvestmentAsPercentageOfSeniorPreferredStockInvestmentOnExerciseOfWarrants" xlink:to="iboc_AggregateCommonStockInvestmentAsPercentageOfSeniorPreferredStockInvestmentOnExerciseOfWarrants_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_AggregateCommonStockInvestmentAsPercentageOfSeniorPreferredStockInvestmentOnExerciseOfWarrants_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">The percentage of aggregate common stock investment on the exercise of warrant to the Senior Preferred Stock investment.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_AggregateCommonStockInvestmentAsPercentageOfSeniorPreferredStockInvestmentOnExerciseOfWarrants_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Aggregate Common Stock Investment As Percentage Of Senior Preferred Stock Investment On Exercise Of Warrants</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_AggregateCommonStockInvestmentAsPercentageOfSeniorPreferredStockInvestmentOnExerciseOfWarrants_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Percentage of aggregate common stock investment on exercise of warrant to Senior Preferred Stock investment</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_ClassOfWarrantOrRightTerm" xlink:label="iboc_ClassOfWarrantOrRightTerm" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_ClassOfWarrantOrRightTerm" xlink:to="iboc_ClassOfWarrantOrRightTerm_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_ClassOfWarrantOrRightTerm_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Period representing the term of warrant.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_ClassOfWarrantOrRightTerm_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Class of Warrant or Right Term</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_ClassOfWarrantOrRightTerm_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Warrants, term</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_MaximumPercentageOfCashDividendsInExcess" xlink:label="iboc_MaximumPercentageOfCashDividendsInExcess" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_MaximumPercentageOfCashDividendsInExcess" xlink:to="iboc_MaximumPercentageOfCashDividendsInExcess_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_MaximumPercentageOfCashDividendsInExcess_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Represents the maximum percentage of cash dividends in excess.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_MaximumPercentageOfCashDividendsInExcess_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Maximum Percentage of Cash dividends in excess</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_MaximumPercentageOfCashDividendsInExcess_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Cash dividends (as a percent)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CommonStockDividendsPerShareCashPaid" xlink:label="us-gaap_CommonStockDividendsPerShareCashPaid" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockDividendsPerShareCashPaid" xlink:to="us-gaap_CommonStockDividendsPerShareCashPaid_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockDividendsPerShareCashPaid_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Common Stock, Dividends, Per Share, Cash Paid</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockDividendsPerShareCashPaid_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Cash dividends paid to common shareholders (in dollars per share)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StockRepurchaseProgramAuthorizedAmount1" xlink:label="us-gaap_StockRepurchaseProgramAuthorizedAmount1" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockRepurchaseProgramAuthorizedAmount1" xlink:to="us-gaap_StockRepurchaseProgramAuthorizedAmount1_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockRepurchaseProgramAuthorizedAmount1_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Stock Repurchase Program, Authorized Amount</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockRepurchaseProgramAuthorizedAmount1_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Repurchase of common stock, authorized amount</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StockRepurchaseProgramPeriodInForce1" xlink:label="us-gaap_StockRepurchaseProgramPeriodInForce1" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockRepurchaseProgramPeriodInForce1" xlink:to="us-gaap_StockRepurchaseProgramPeriodInForce1_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockRepurchaseProgramPeriodInForce1_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Stock Repurchase Program, Period in Force</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockRepurchaseProgramPeriodInForce1_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Period of repurchase of common stock</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_StockRepurchaseProgramCumulativeSharesRepurchased" xlink:label="iboc_StockRepurchaseProgramCumulativeSharesRepurchased" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_StockRepurchaseProgramCumulativeSharesRepurchased" xlink:to="iboc_StockRepurchaseProgramCumulativeSharesRepurchased_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_StockRepurchaseProgramCumulativeSharesRepurchased_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">The cumulative number of shares that have been repurchased under all stock repurchase programs as of a certain date.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_StockRepurchaseProgramCumulativeSharesRepurchased_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Stock Repurchase Program Cumulative Shares Repurchased</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_StockRepurchaseProgramCumulativeSharesRepurchased_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Cumulative number of shares repurchased under all stock repurchase programs</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_StockRepurchaseProgramCumulativeCostOfSharesRepurchased" xlink:label="iboc_StockRepurchaseProgramCumulativeCostOfSharesRepurchased" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_StockRepurchaseProgramCumulativeCostOfSharesRepurchased" xlink:to="iboc_StockRepurchaseProgramCumulativeCostOfSharesRepurchased_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_StockRepurchaseProgramCumulativeCostOfSharesRepurchased_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">The cumulative cost of shares that have been repurchased under all stock repurchase programs as of a certain date.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_StockRepurchaseProgramCumulativeCostOfSharesRepurchased_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Stock Repurchase Program Cumulative Cost Of Shares Repurchased</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_StockRepurchaseProgramCumulativeCostOfSharesRepurchased_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Cumulative cost of shares repurchased under all stock repurchase programs</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_RangeAxis" xlink:label="us-gaap_RangeAxis" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RangeAxis" xlink:to="us-gaap_RangeAxis_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RangeAxis_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Range [Axis]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_RangeMember" xlink:label="us-gaap_RangeMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RangeMember" xlink:to="us-gaap_RangeMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RangeMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Range [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RangeMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Range [Domain]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_MinimumMember" xlink:label="us-gaap_MinimumMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MinimumMember" xlink:to="us-gaap_MinimumMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MinimumMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Minimum [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_MinimumMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Minimum</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_CommonEquityTierOneRatio" xlink:label="iboc_CommonEquityTierOneRatio" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_CommonEquityTierOneRatio" xlink:to="iboc_CommonEquityTierOneRatio_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_CommonEquityTierOneRatio_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Represents information pertaining to Common Equity Tier 1 ("CET1")ratio.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_CommonEquityTierOneRatio_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Common Equity Tier One Ratio</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_CommonEquityTierOneRatio_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">CET 1 ratio</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_TierOneLeverageCapitalToAverageAssets" xlink:label="us-gaap_TierOneLeverageCapitalToAverageAssets" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TierOneLeverageCapitalToAverageAssets" xlink:to="us-gaap_TierOneLeverageCapitalToAverageAssets_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TierOneLeverageCapitalToAverageAssets_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Tier One Leverage Capital to Average Assets</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TierOneLeverageCapitalToAverageAssets_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Tier 1 capital (to Average Assets), Actual Ratio (as a percent)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets" xlink:label="us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets" xlink:to="us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Tier One Risk Based Capital to Risk Weighted Assets</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Tier 1 capital (to Risk Weighted Assets), Actual Ratio (as a percent)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CapitalToRiskWeightedAssets" xlink:label="us-gaap_CapitalToRiskWeightedAssets" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CapitalToRiskWeightedAssets" xlink:to="us-gaap_CapitalToRiskWeightedAssets_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CapitalToRiskWeightedAssets_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Capital to Risk Weighted Assets</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CapitalToRiskWeightedAssets_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total Capital (to Risk Weighted Assets), Actual Ratio (as a percent)</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets" xlink:label="us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets" xlink:to="us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Capital Required for Capital Adequacy to Risk Weighted Assets</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Total Capital (to Risk Weighted Assets), For Capital Adequacy Purposes Ratio (as a percent)</label>
    <loc xlink:type="locator" xlink:href="iboc-20160630.xsd#iboc_MandatoryComplianceTerm" xlink:label="iboc_MandatoryComplianceTerm" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="iboc_MandatoryComplianceTerm" xlink:to="iboc_MandatoryComplianceTerm_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="iboc_MandatoryComplianceTerm_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Period representing the new rule of mandatory compliance.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="iboc_MandatoryComplianceTerm_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Mandatory compliance Term</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="iboc_MandatoryComplianceTerm_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Term of mandatory compliance</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FairValueByMeasurementBasisAxis" xlink:label="us-gaap_FairValueByMeasurementBasisAxis" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueByMeasurementBasisAxis_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Measurement Basis [Axis]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FairValueDisclosureItemAmountsDomain" xlink:label="us-gaap_FairValueDisclosureItemAmountsDomain" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueDisclosureItemAmountsDomain" xlink:to="us-gaap_FairValueDisclosureItemAmountsDomain_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueDisclosureItemAmountsDomain_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value Disclosure Item Amounts [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueDisclosureItemAmountsDomain_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Fair Value Measurement [Domain]</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember" xlink:label="us-gaap_EstimateOfFairValueFairValueDisclosureMember" xmlns="http://www.xbrl.org/2003/linkbase" />
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EstimateOfFairValueFairValueDisclosureMember" xlink:to="us-gaap_EstimateOfFairValueFairValueDisclosureMember_lbl" xmlns="http://www.xbrl.org/2003/linkbase" />
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EstimateOfFairValueFairValueDisclosureMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Estimate Of Fair Value Fair Value Disclosure [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EstimateOfFairValueFairValueDisclosureMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Assets/liabilities measured at fair value</label>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CarryingReportedAmountFairValueDisclosureMember" xlink:label="us-gaap_CarryingReportedAmountFairValueDisclosureMember" xmlns="http://www.xbrl.org/2003/linkbase" />
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CarryingReportedAmountFairValueDisclosureMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Carrying Reported Amount Fair Value Disclosure [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CarryingReportedAmountFairValueDisclosureMember_lbl" xml:lang="en-US" xmlns="http://www.xbrl.org/2003/linkbase">Carrying Value</label>
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