Loan Servicing Rights - Additional Information (Detail) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Servicing Assets at Fair Value [Line Items]
Fair value of servicing rights	$ 1,134,000us-gaap_ServicingAsset	$ 614,000us-gaap_ServicingAsset
Servicing rights, weighted average default rate	0.70%	2.62%
Minimum [Member]
Servicing Assets at Fair Value [Line Items]
Servicing rights, discount rates range	9.50%	10.50%
Servicing Rights, prepayment speeds range	11.10%	8.50%
Maximum [Member]
Servicing Assets at Fair Value [Line Items]
Servicing rights, discount rates range	12.00%	13.00%
Servicing Rights, prepayment speeds range	24.70%	24.70%

Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

+ Details

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- Definition

Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 50

-Paragraph 2

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122596-111746

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- Definition

Percentage of contractually collectible principal associated with a financial asset expected not to be collected due to default by the borrower.

+ References

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- Definition

Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

+ References

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