Valuation Techniques, Significant Unobservable Inputs, Quantitative Information Non-recurring Basis (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial Instrument, fair value	$ 10.4	$ 14.2
Loans \| Fair Value, Inputs, Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial Instrument, fair value	$ 10.4
Valuation Technique	Market Approach
Unobservable Input	Discount to reflect realizable value
Loans \| Lower Limit \| Fair Value, Inputs, Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Range of Discounts Applied	15.00%
Loans \| Upper Limit \| Fair Value, Inputs, Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Range of Discounts Applied	25.00%
OREO
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial Instrument, fair value	$ 3.6	$ 4.1
OREO \| Fair Value, Inputs, Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial Instrument, fair value	$ 3.6
Valuation Technique	Market Approach
Unobservable Input	Discount to reflect realizable value
OREO \| Lower Limit \| Fair Value, Inputs, Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Range of Discounts Applied	15.00%
OREO \| Upper Limit \| Fair Value, Inputs, Level 3
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

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.

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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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