Fair Value Measurement of Assets and Liabilities - Assets and Liabilities Measured at Fair Value on Recurring and Non-Recurring Basis (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Unpaid principal balances of loans held for sale	$ 4,500		$ 4,500		$ 16,900
Change in fair value of loans held for sale	53	$ 252	153	$ 372
Covered real estate owned	$ 2,900		$ 2,900		$ 3,200

Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- References

No definition available.

+ Details

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- Definition

Carrying amount of other real estate covered by loss sharing agreements not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations that may also be included in real estate owned. Excludes real estate assets taken in settlement of troubled loans through surrender or foreclosure by banks.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

This is the principal amount outstanding for loans which are in the process of being securitized as of the date of the statement of financial position (across all types of loans).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=51814546&loc=d3e107314-111719

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