XML 27 R76.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Capital and Regulatory Matters - Additional Information (Detail) (USD $) | 3 Months Ended | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Mar. 31, 2015 quarter | Mar. 31, 2016 | Feb. 28, 2007 | Dec. 31, 2014 | Jan. 01, 2019
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |
Preferred stock value issued include for regulatory tier one capital calculations | $ 144,500,000 cfr_PreferredStockValueIssuedIncludeForRegulatoryTierOneCapitalCalculations |  |  |  |
Preferred stock dividend rate percentage | 5.375%us-gaap_PreferredStockDividendRatePercentage |  |  |  |
Trust preferred securities | 133,000,000 us-gaap_ProceedsFromIssuanceOfTrustPreferredSecurities |  |  |  |
Corporation's aggregate subordinated notes | 137,115,000 us-gaap_JuniorSubordinatedNotes |  |  | 137,115,000 us-gaap_JuniorSubordinatedNotes |
Maximum dividends available without prior regulatory approval | 307,700,000 us-gaap_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval |  |  |  |
Maximum number of quarterly periods by which the corporation has the right to defer interest payments on junior subordinated deferrable interest debentures | 20 cfr_Maximumnumberofquarterlyperiodsbywhichthecorporationhastherighttodeferinterestpaymentsonjuniorsubordinateddeferrableinterestdebentures |  |  |  |
Two Thousand And Fifteen [Member] | Scenario, Forecast [Member] |  |  |  |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |
Minimum ratio of Tier 1 capital to risk-weighted assets |  |  |  |  | 6.00%us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets / us-gaap_CreationDateAxis = cfr_TwoThousandAndFifteenMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioForecastMember
Minimum ratio of Total capital to risk-weighted assets |  |  |  |  | 8.00%us-gaap_CapitalToRiskWeightedAssets / us-gaap_CreationDateAxis = cfr_TwoThousandAndFifteenMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioForecastMember
Common Equity Tier 1 Risk Based Capital To Risk Weighted Assets |  |  |  |  | 4.50%cfr_CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredBaselIIIPhaseInSchedule / us-gaap_CreationDateAxis = cfr_TwoThousandAndFifteenMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioForecastMember
Two Thousand And Fifteen [Member] | Scenario, Forecast [Member] | Minimum [Member] |  |  |  |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |
Effective Tier 1 Capital Ratio, Upon Full Implementation |  |  |  |  | 8.50%cfr_EffectiveTierOneCapitalRatio / us-gaap_CreationDateAxis = cfr_TwoThousandAndFifteenMember / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioForecastMember
Tier One Risk Based Capital to Risk Weighted Assets, Ratio Upon Full Implementation |  |  |  |  | 10.50%us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets / us-gaap_CreationDateAxis = cfr_TwoThousandAndFifteenMember / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioForecastMember
Minimum leverage ratio |  |  |  |  | 4.00%us-gaap_TierOneLeverageCapitalToAverageAssets / us-gaap_CreationDateAxis = cfr_TwoThousandAndFifteenMember / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioForecastMember
Effective Common Equity Tier One Capital To Risk Weighted Assets, Ratio Upon Full Implementation |  |  |  |  | 7.00%cfr_EffectiveFullyImplementedCommonEquityTierOneRiskBasedCapitalToRiskWeightedAssets / us-gaap_CreationDateAxis = cfr_TwoThousandAndFifteenMember / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioForecastMember
Two Thousand And Sixteen [Member] | Scenario, Forecast [Member] |  |  |  |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |
Tier One Capital Conservation Buffer To Risk Weighted Assets Required Under Regulatory |  | 0.625%cfr_TierOneCapitalConservationBufferToRiskWeightedAssetsRequiredUnderRegulatory / us-gaap_CreationDateAxis = cfr_TwoThousandAndSixteenMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioForecastMember |  |  |
Tier One Risk Based Capital Conservation Buffer Initial Requirements Phasing Duration |  | 4 years |  |  |
Capital Conservation Buffer |  |  |  |  | 2.50%cfr_CapitalConservationBuffer / us-gaap_CreationDateAxis = cfr_TwoThousandAndSixteenMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioForecastMember
Trust Preferred Securities Tier One Allowable Portion [Member] |  |  |  |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |
Trust preferred securities | 33,300,000 us-gaap_ProceedsFromIssuanceOfTrustPreferredSecurities / us-gaap_DebtInstrumentAxis = cfr_TrustPreferredSecuritiesTierOneAllowablePortionMember |  |  |  |
Trust Preferred Securities Tier One Excluded Portion [Member] |  |  |  |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |
Trust preferred securities | 99,700,000 us-gaap_ProceedsFromIssuanceOfTrustPreferredSecurities / us-gaap_DebtInstrumentAxis = cfr_TrustPreferredSecuritiesTierOneExcludedPortionMember |  |  |  |
Floating Rate Subordinated Notes [Member] |  |  |  |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |
Corporation's aggregate subordinated notes | 100,000,000 us-gaap_JuniorSubordinatedNotes / us-gaap_DebtInstrumentAxis = cfr_FloatingRateSubordinatedNotesMember |  |  |  |
Per Year Percentage decrease in permissible portion of subordinate note included in Total Capital | 20.00%cfr_PermissiblePercentageDecreasedEachOfFinalFiveYearsOfTermOfNotes / us-gaap_DebtInstrumentAxis = cfr_FloatingRateSubordinatedNotesMember |  |  |  |
Final years of the term of the notes | 5 years |  |  |  |
Debt Instrument, Maturity Date |  |  | Feb. 15, 2017 |  |
Permissible portion of subordinated note included in total capital | 20,000,000 cfr_PermissiblePortionOfSubordinatedNotesIncludedInCapital / us-gaap_DebtInstrumentAxis = cfr_FloatingRateSubordinatedNotesMember |  |  | 40,000,000 cfr_PermissiblePortionOfSubordinatedNotesIncludedInCapital / us-gaap_DebtInstrumentAxis = cfr_FloatingRateSubordinatedNotesMember |
Floating Rate Subordinated Notes [Member] | Two Thousand And Sixteen [Member] | Scenario, Forecast [Member] |  |  |  |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |
Permissible portion of subordinated note included in total capital |  | 0 cfr_PermissiblePortionOfSubordinatedNotesIncludedInCapital / us-gaap_CreationDateAxis = cfr_TwoThousandAndSixteenMember / us-gaap_DebtInstrumentAxis = cfr_FloatingRateSubordinatedNotesMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioForecastMember |  |  |
Cullen/Frost [Member] |  |  |  |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |
Minimum ratio of Tier 1 capital to risk-weighted assets |  |  |  | 4.00%us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets / dei_LegalEntityAxis = cfr_CullenFrostMember |
Minimum ratio of Total capital to risk-weighted assets | 13.93%us-gaap_CapitalToRiskWeightedAssets / dei_LegalEntityAxis = cfr_CullenFrostMember |  |  | 14.55%us-gaap_CapitalToRiskWeightedAssets / dei_LegalEntityAxis = cfr_CullenFrostMember |
Minimum leverage ratio | 7.89%us-gaap_TierOneLeverageCapitalToAverageAssets / dei_LegalEntityAxis = cfr_CullenFrostMember |  |  | 8.16%us-gaap_TierOneLeverageCapitalToAverageAssets / dei_LegalEntityAxis = cfr_CullenFrostMember |
Common Equity Tier 1 Risk Based Capital To Risk Weighted Assets | 4.50%cfr_CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredBaselIIIPhaseInSchedule / dei_LegalEntityAxis = cfr_CullenFrostMember |  |  |  |

X
- Definition Capital Conservation Buffer + References No definition available. + Details
Name: | cfr_CapitalConservationBuffer
Namespace Prefix: | cfr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Common Equity Tier One Risk Based Capital To Risk Weighted Assets Minimum Capital Required Basel III Phase In Schedule + References No definition available. + Details
Name: | cfr_CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredBaselIIIPhaseInSchedule
Namespace Prefix: | cfr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Effective Fully Implemented Common Equity Tier One Risk Based Capital To Risk Weighted Assets. + References No definition available. + Details
Name: | cfr_EffectiveFullyImplementedCommonEquityTierOneRiskBasedCapitalToRiskWeightedAssets
Namespace Prefix: | cfr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Effective Tier One Capital Ratio + References No definition available. + Details
Name: | cfr_EffectiveTierOneCapitalRatio
Namespace Prefix: | cfr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Final years of the term of the notes + References No definition available. + Details
Name: | cfr_Finalyearsofthetermofthenotes
Namespace Prefix: | cfr_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Maximum number of quarterly periods by which the corporation has the right to defer interest payments on junior subordinated deferrable interest debentures + References No definition available. + Details
Name: | cfr_Maximumnumberofquarterlyperiodsbywhichthecorporationhastherighttodeferinterestpaymentsonjuniorsubordinateddeferrableinterestdebentures
Namespace Prefix: | cfr_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Permissible Percentage Decreased Each Of Final Five Years Of Term Of Notes + References No definition available. + Details
Name: | cfr_PermissiblePercentageDecreasedEachOfFinalFiveYearsOfTermOfNotes
Namespace Prefix: | cfr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Permissible Portion Of Subordinated Notes Included In Capital + References No definition available. + Details
Name: | cfr_PermissiblePortionOfSubordinatedNotesIncludedInCapital
Namespace Prefix: | cfr_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Preferred Stock Value Issued Include For Regulatory Tier One capital calculations + References No definition available. + Details
Name: | cfr_PreferredStockValueIssuedIncludeForRegulatoryTierOneCapitalCalculations
Namespace Prefix: | cfr_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Tier One Capital Conservation Buffer to Risk Weighted Assets Required under Regulatory + References No definition available. + Details
Name: | cfr_TierOneCapitalConservationBufferToRiskWeightedAssetsRequiredUnderRegulatory
Namespace Prefix: | cfr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tier One Risk Based Capital Conservation Buffer Initial Requirements Phasing Duration + References No definition available. + Details
Name: | cfr_TierOneRiskBasedCapitalConservationBufferInitialRequirementsPhasingDuration
Namespace Prefix: | cfr_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Total Capital divided by risk weighted assets as defined in the regulations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 + Details
Name: | us-gaap_CapitalToRiskWeightedAssets
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentMaturityDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments. + References 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 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16(a)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 13, 16 -Article 9 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_JuniorSubordinatedNotes
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The percentage rate used to calculate dividend payments on preferred stock. + References No definition available. + Details
Name: | us-gaap_PreferredStockDividendRatePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The cash inflow from issuance of preferred stocks by a business trust or other special purpose entity, mainly established by a bank holding entity, to third party investors. The trust's assets are deeply subordinated debentures of the bank holding entity. Most trust preferred securities are subject to a mandatory redemption upon the repayment of the debentures. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromIssuanceOfTrustPreferredSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of dividends that can be declared or paid without approval of regulatory agency. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(e)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
Name: | us-gaap_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Tier 1 Leverage Capital divided by average assets as defined in the regulations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 + Details
Name: | us-gaap_TierOneLeverageCapitalToAverageAssets
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958570-112826 + Details
Name: | us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Tier 1 capital divided by risk weighted assets as defined by regulations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 + Details
Name: | us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | dei_LegalEntityAxis=cfr_CullenFrostMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CreationDateAxis=cfr_TwoThousandAndFifteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CreationDateAxis=cfr_TwoThousandAndSixteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cfr_FloatingRateSubordinatedNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cfr_TrustPreferredSecuritiesTierOneAllowablePortionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cfr_TrustPreferredSecuritiesTierOneExcludedPortionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |