Capital Conservation Buffer

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- Definition

Common Equity Tier One Risk Based Capital To Risk Weighted Assets Minimum Capital Required Basel III Phase In Schedule

+ References

No definition available.

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- Definition

Effective Fully Implemented Common Equity Tier One Risk Based Capital To Risk Weighted Assets.

+ References

No definition available.

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- Definition

Effective Tier One Capital Ratio

+ References

No definition available.

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- Definition

Final years of the term of the notes

+ References

No definition available.

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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

Permissible Percentage Decreased Each Of Final Five Years Of Term Of Notes

+ References

No definition available.

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- Definition

Permissible Portion Of Subordinated Notes Included In Capital

+ 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

Tier One Capital Conservation Buffer to Risk Weighted Assets Required under Regulatory

+ References

No definition available.

+ Details

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- Definition

Tier One Risk Based Capital Conservation Buffer Initial Requirements Phasing Duration

+ References

No definition available.

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- Definition

Total Capital divided by risk weighted assets as defined in the regulations.

+ References

+ Details

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- 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

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- 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

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- Definition

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

+ References

No definition available.

+ Details

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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.

+ 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

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- 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

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- Definition

Tier 1 Leverage Capital divided by average assets as defined in the regulations.

+ References

+ Details

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- 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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 505

-Section 50

-Paragraph 1

-Subparagraph (c)(1)

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-Topic 942

-SubTopic 505

-Section 50

-Paragraph 1B

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- Definition

Tier 1 capital divided by risk weighted assets as defined by regulations.

+ References

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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
Preferred stock dividend rate percentage	5.375%
Trust preferred securities	133,000,000
Corporation's aggregate subordinated notes	137,115,000us-gaap_JuniorSubordinatedNotes			137,115,000us-gaap_JuniorSubordinatedNotes
Maximum dividends available without prior regulatory approval	307,700,000
Maximum number of quarterly periods by which the corporation has the right to defer interest payments on junior subordinated deferrable interest debentures	20
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%
Minimum ratio of Total capital to risk-weighted assets					8.00%
Common Equity Tier 1 Risk Based Capital To Risk Weighted Assets					4.50%
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%
Tier One Risk Based Capital to Risk Weighted Assets, Ratio Upon Full Implementation					10.50%
Minimum leverage ratio					4.00%
Effective Common Equity Tier One Capital To Risk Weighted Assets, Ratio Upon Full Implementation					7.00%
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%
Tier One Risk Based Capital Conservation Buffer Initial Requirements Phasing Duration		4 years
Capital Conservation Buffer					2.50%
Trust Preferred Securities Tier One Allowable Portion [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Trust preferred securities	33,300,000
Trust Preferred Securities Tier One Excluded Portion [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Trust preferred securities	99,700,000
Floating Rate Subordinated Notes [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Corporation's aggregate subordinated notes	100,000,000
Per Year Percentage decrease in permissible portion of subordinate note included in Total Capital	20.00%
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			40,000,000
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
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%
Minimum ratio of Total capital to risk-weighted assets	13.93%			14.55%
Minimum leverage ratio	7.89%			8.16%
Common Equity Tier 1 Risk Based Capital To Risk Weighted Assets	4.50%