Impaired Loans (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Impaired Loans:
Impaired loans without a valuation allowance	$ 4,906	$ 4,702
Impaired loans with a valuation allowance	3,717	4,858
Total impaired loans	8,623	9,560
Allowance for loan losses on impaired loans at period End	936	968
Total nonaccrual loans	5,995	6,056	33,000
Past due 90 days or more and still accruing	426	669
Average investment in impaired loans	$ 9,092	$ 7,077

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

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

-Publisher FASB

-Name Accounting Standards Codification

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

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Amount of allowance for credit losses related to recorded investment.

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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