Valuation Techniques, Significant Unobservable Inputs, Quantitative Information Non-recurring Basis (Detail) (Fair Value, Inputs, Level 3, USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015
Loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial Instrument, fair value	$ 23.1
Valuation Technique	Market Approach
Unobservable Input	Discount to reflect realizable value
Other Real Estate Owned
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial Instrument, fair value	$ 0.3
Valuation Technique	Market Approach
Unobservable Input	Discount to reflect realizable value
Lower Limit \| Loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Range of Discounts Applied	15.00%
Lower Limit \| Other Real Estate Owned
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Range of Discounts Applied	15.00%
Upper Limit \| Loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Range of Discounts Applied	25.00%
Upper Limit \| Other Real Estate Owned
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Range of Discounts Applied	20.00%

Fair Value Assets And Liabilities Measured On Non Recurring Basis Significant Unobservable Inputs

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- Definition

Fair Value, Measurement with Unobservable Inputs Reconciliation, NonRecurring Basis, Asset and Liabilities

+ References

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- Definition

Discount applied to the valuation to reflect net realizable value of the financial instrument.

+ References

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- Definition

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)

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

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