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Fair Value Measurements - Quantitative Information about Level 3 Fair Value Measurements (Detail) - Fair Value, Measurements, Nonrecurring [Member] - Significant Unobservable Inputs (Level 3) [Member] - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Impaired Loans Asset, Net [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value assets	$ 1,899	$ 2,976
Fair Value Measurements, Valuation Techniques	Property appraisals	Property appraisals
Selling cost	7.00%	10.00%
Property condition	1.00%
Impaired Loans Asset, Net [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling cost	0.00%
Property condition	0.00%
Impaired Loans Asset, Net [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Selling cost	10.00%
Property condition	13.00%
Other Real Estate Owned, Net [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value assets	$ 2,407	$ 1,888
Fair Value Measurements, Valuation Techniques	Property appraisals	Property appraisals
Selling cost	7.00%	7.00%
Property condition	2.00%
Other Real Estate Owned, Net [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Property condition	0.00%
Other Real Estate Owned, Net [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Property condition	7.00%

X

- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ 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 (a)



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

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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

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- Definition

Percentage of adjustment to the observed price for a similar asset or liability when an identical transaction does not exist, used as an input to measure fair value.

+ 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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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)



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Description of the inputs and valuation technique(s) used to measure fair value.

+ 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)



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