Fair Values - Assets and Liabilities Measured at Fair Value on Nonrecurring Basis (Detail) (Nonrecurring basis [Member], USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total assets measured at fair value	$ 2,317	$ 13,796
Collateral dependent impaired loans [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total assets measured at fair value	2,317	12,865
Other real estate owned [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total assets measured at fair value		931
Level 1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total assets measured at fair value	0	0
Level 1 [Member] | Collateral dependent impaired loans [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total assets measured at fair value	0	0
Level 1 [Member] | Other real estate owned [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total assets measured at fair value		0
Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total assets measured at fair value	0	0
Level 2 [Member] | Collateral dependent impaired loans [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total assets measured at fair value	0	0
Level 2 [Member] | Other real estate owned [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total assets measured at fair value		0
Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total assets measured at fair value	2,317	13,796
Level 3 [Member] | Collateral dependent impaired loans [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total assets measured at fair value	2,317	12,865
Level 3 [Member] | Other real estate owned [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total assets measured at fair value		$ 931