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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.

No definition available.

Name:	iboc_LoansReceivableWithFixedRateOfInterestFairValueDisclosure
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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.

No definition available.

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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.

No definition available.

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64702-112823

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Amount of loan with fixed rate of interest.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

Name:	us-gaap_LoansReceivableWithFixedRatesOfInterest1
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Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13433-108611

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Amount of deposits that cannot be withdrawn before a set date without penalty or for which notice of withdrawal is required. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.12)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Article 9

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