Junior Subordinated Debt - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	1 Months Ended	3 Months Ended	12 Months Ended
Jun. 30, 2013	Dec. 31, 2013 Trust	Jun. 30, 2013	Dec. 31, 2013 Trust
Debt Disclosure [Abstract]
Number of unconsolidated subsidiary trusts		3		3
Percent of the common equity of each Trust owned by the Corporation		100.00%		100.00%
Increased total assets		$ 15,000,000		$ 15,000,000
Amount of TPS repurchased	15,000		15,000	15,000
Redeemed value of TPS		(115,000)		(134,021)
Debt extinguishment of TPS		$ 130,000

Number of unconsolidated subsidiary trusts.

No definition available.

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- Definition

Percentage of each trust common equity owned by corporation

+ References

No definition available.

+ Details

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- Definition

Threshold limit for asset related to trust preferred securities obligations.

+ References

No definition available.

+ Details

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- Details

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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- Definition

The cash outflow to reacquire preferred stocks issued 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

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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- Definition

The cash inflow from issuance of trust preferred securities, net of the cash outflow for repurchasing trust preferred securities, 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

+ Details

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