Securities - Summary Other Than Temporary Impairment Losses on Securities (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2013
Schedule of Available-for-sale Securities [Line Items]
Total other-than-temporary impairment losses	$ 511	$ 511
Less: unrealized other-than-temporary losses recognized in accumulated other comprehensive loss		111
Net impairment losses recognized in earnings		400
Trust Preferred Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Total other-than-temporary impairment losses		511
Less: unrealized other-than-temporary losses recognized in accumulated other comprehensive loss		111
Net impairment losses recognized in earnings		$ 400

The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

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- Definition

Amount after tax of other than temporary impairment (OTTI) on investment in available-for-sale debt security, recognized in other comprehensive loss, attributable to parent entity.

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- Definition

The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

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