Fair Value of Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Transfer out of Level 3 to Level 2		$ 27
Non-agency CMOs
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Transfer out of Level 3 to Level 2		$ 27
Mortgage Servicing Rights
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	11.35%
Mortgage Servicing Rights \| Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	11.00%
Total portfolio lifetime weighted average prepayment speeds	6.67%
Mortgage Servicing Rights \| Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	20.00%
Total portfolio lifetime weighted average prepayment speeds	39.90%

Portfolio lifetime weighted average prepayment speeds.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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