Fair Values of Financial Instruments - Unobservable Inputs Used in Recurring and Nonrecurring Level 3 Fair Value Measurements Other Than Goodwill (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Discounted Cash Flow | State and municipal securities
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value	$ 7,235
Discounted Cash Flow | State and municipal securities | Minimum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Maturity/Call date	1 month
Discount rate	1.00%
Discounted Cash Flow | State and municipal securities | Maximum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Maturity/Call date	15 years
Blend of US Muni BQ curve	BBB-
Discount rate	5.00%
Discounted Cash Flow | Corporate Bonds and Notes
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value	2,742
Discounted Cash Flow | 3 month libor | Corporate Bonds and Notes
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Premium for illiquidity	2.00%
Collateral Based Measurements | Impaired loans (collateral dependent)
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value	12,117
Collateral Based Measurements | Impaired loans (collateral dependent) | Minimum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount to reflect current market conditions and ultimate collectability	0.00%
Collateral Based Measurements | Impaired loans (collateral dependent) | Maximum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount to reflect current market conditions and ultimate collectability	50.00%
Collateral Based Measurements | Impaired loans (collateral dependent) | Weighted Average
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount to reflect current market conditions and ultimate collectability	3.00%
Appraisals | Other real estate owned
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value	$ 6,877
Appraisals | Other real estate owned | Minimum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount to reflect current market conditions	0.00%
Appraisals | Other real estate owned | Maximum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount to reflect current market conditions	20.00%
Appraisals | Other real estate owned | Weighted Average
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount to reflect current market conditions	2.00%