Additional Tier 1 Capital beyond Common Equity Tier 1

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- 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.

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- Definition

Preferred Stock Value Issued Include For Regulatory Tier One capital calculations

+ References

No definition available.

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- 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.

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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

+ References

No definition available.

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- 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.

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- Definition

Amount of dividends that can be declared or paid without approval of regulatory agency.

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- 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.

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No definition available.

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- 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.

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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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