Fair Value Measurements - Assets Measured at Fair Value on Nonrecurring Basis (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Impaired loans (less specific allowance) [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value	$ 34,848	$ 40,681
Gains (Losses)
Foreclosed Assets [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value	237	339
Gains (Losses)	(35)	(118)
Other real estate owned [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value	8,149	9,227
Gains (Losses)	(170)	(1,328)
Level 1 Inputs [Member] | Impaired loans (less specific allowance) [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value
Level 1 Inputs [Member] | Foreclosed Assets [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value
Level 1 Inputs [Member] | Other real estate owned [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value
Level 2 Inputs [Member] | Impaired loans (less specific allowance) [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value
Level 2 Inputs [Member] | Foreclosed Assets [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value
Level 2 Inputs [Member] | Other real estate owned [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value
Level 3 Inputs [Member] | Impaired loans (less specific allowance) [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value	34,848	40,681
Level 3 Inputs [Member] | Foreclosed Assets [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value	237	339
Level 3 Inputs [Member] | Other real estate owned [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value	$ 8,149	$ 9,227