Securities - Fair Market Value of Securities Held (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Total securities held for pledging purposes	$ 43,752
Public funds collateral [Member]
Schedule of Available-for-sale Securities [Line Items]
Total securities held for pledging purposes	21,706
Federal Home Loan Bank borrowings [Member]
Schedule of Available-for-sale Securities [Line Items]
Total securities held for pledging purposes	16,505
Interest rate swap contracts [Member]
Schedule of Available-for-sale Securities [Line Items]
Total securities held for pledging purposes	$ 5,541