XML 86 R74.htm IDEA: XBRL DOCUMENT
v3.19.2

Capital and Regulatory Matters - Additional Information (Detail) $ in Thousands |  |  | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Jul. 24, 2019 USD ($) | Oct. 24, 2017 USD ($) | Jun. 30, 2019 USD ($) shares | Dec. 31, 2018 USD ($) shares | Jun. 30, 2018 USD ($) shares | Jun. 30, 2019 USD ($) quarter shares | Jun. 30, 2018 USD ($) shares | Dec. 31, 2018 USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |  |  |  |
Stock Repurchase Program, Authorized Amount | $ 100,000 | $ 150,000 |  |  |  |  |  |
Stock Repurchase Program, Period in Force | 1 year | 2 years |  |  |  |  |  |
Treasury stock, shares, acquired | shares |  |  | 496,307 |  | 601 | 501,658 | 601 |
Treasury Stock, Value, Acquired, Cost Method |  |  | $ (50,000) |  | $ (70) | $ (50,519) | $ (70) |
Qualified subordinated debt |  |  | 98,786 | $ 98,708 |  | 98,786 |  | $ 98,708
Maximum dividends available without prior regulatory approval |  |  | 577,300 |  |  | $ 577,300 |  |
Maximum number of quarterly periods by which the corporation has the right to defer interest payments on junior subordinated deferrable interest debentures | quarter |  |  |  |  |  | 20 |  |
Trust Preferred Securities Tier One Excluded Portion [Member] |  |  |  |  |  |  |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |  |  |  |
Trust preferred securities |  |  |  |  |  | $ 133,000 |  | 133,000
Cullen/Frost [Member] |  |  |  |  |  |  |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |  |  |  |
Preferred stock value issued include for regulatory tier one capital calculations |  |  | 144,500 | 144,500 |  | $ 144,500 |  | $ 144,500
Preferred stock dividend rate percentage |  |  |  |  |  | 5.375% |  | 5.375%
Frost Bank [Member] |  |  |  |  |  |  |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |  |  |  |
Additional Tier 1 Capital beyond Common Equity Tier 1 |  |  | $ 0 | $ 0 |  | $ 0 |  | $ 0
Stock Repurchase 2017 Plan | Treasury Stock [Member] |  |  |  |  |  |  |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |  |  |  |
Treasury stock, shares, acquired | shares |  |  | 496,307 | 1,027,292 |  |  |  |
Treasury Stock, Value, Acquired, Cost Method |  |  | $ (50,000) | $ (100,000) |  |  |  |
Subordinated Debt [Member] |  |  |  |  |  |  |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |  |  |  |  |  |  |
Qualified subordinated debt |  |  | $ 100,000 | $ 100,000 |  | $ 100,000 |  | $ 100,000

X
- Definition Additional Tier 1 Capital beyond Common Equity Tier 1 + References No definition available. + Details
Name: | cfr_AdditionalTier1CapitalbeyondCommonEquityTier1
Namespace Prefix: | cfr_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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 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 Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&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://fasb.org/us-gaap/role/ref/legacyRef -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 Amount of stock repurchase plan authorized. + References No definition available. + Details
Name: | us-gaap_StockRepurchaseProgramAuthorizedAmount1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Period which shares may be purchased under a stock repurchase plan authorized by an entity's Board of Directors, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_StockRepurchaseProgramPeriodInForce1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(19)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_SubordinatedDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Number of shares that have been repurchased during the period and are being held in treasury. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_TreasuryStockSharesAcquired
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
Name: | us-gaap_TreasuryStockValueAcquiredCostMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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

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

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

X
- Details
Name: | us-gaap_ShareRepurchaseProgramAxis=cfr_Stockrepurchase2017planMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_TreasuryStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_SubordinatedDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |