Valuation Techniques, Significant Unobservable Inputs, Quantitative Information Non-recurring Basis (Detail) (Fair Value, Inputs, Level 3, USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2014
Loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial Instrument, fair value	$ 26.6
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	$ 1.5
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%