Income Taxes - Components of Deferred Income Taxes (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Deferred tax assets:
Allowance for loan losses	$ 7,832,000	$ 8,258,000
Deferred compensation	550,000	276,000
Deferred gain on interest rate swap	573,000	686,000
Unrealized loss on interest rate swap	130,000	1,042,000
Unrealized loss on securities available for sale	911,000
Nonaccrual interest	323,000	891,000
Purchase accounting adjustments	26,408,000
Other real estate owned	1,855,000	3,803,000
Capitalized costs, accrued expenses and other	1,976,000	1,155,000
Deferred tax assets	40,558,000	16,111,000
Deferred tax liabilities:
Depreciation and amortization	4,355,000	4,758,000
Intangible assets		60,000
Purchase accounting adjustments	7,534,000
Deferred gain on FDIC-assisted transactions	12,218,000	17,256,000
Unrealized gain on securities available for sale		3,570,000
Deferred tax liabilities	24,107,000	25,644,000
Net deferred tax asset (liability)	$ 16,451,000	$ (9,533,000)