Other Real Estate Owned (OREO) - Summary of Changes in the Valuation Allowance (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Real Estate [Abstract]
Balance at beginning of year	$ 375	$ 1,665	$ 1,665
Provision for losses		23	12
Charge-offs, net	(250)	(2)	(1,302)
Balance at end of period	$ 125	$ 1,686	$ 375

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For each period for which an income statement is required, disclosure of the changes in the allowance, including balances at end of period.

+ 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 210.9-03.10(4))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 10

-Subparagraph 4

-Article 9

+ Details

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- Definition

Amount of the valuation allowance for real estate owned that was applied in the period against the carrying amount of real estate owned that was sold, written down or written off.

+ References

+ Details

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- Definition

Amount of expense recognized in the income statement for a decrease in valuation of real estate owned (REO).

+ References

+ Details

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