Quarterly Financial Information - Summary of Quarterly Data (Parenthetical) (Detail) (USD $)	3 Months Ended						12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Quarterly Financial Information Disclosure [Abstract]
Decrease in provision for loan losses		$ 1,900,000
Recognized tax benefit	(300,000)	350,000	150,000		1,950,000	(2,838,000)	200,000	(888,000)
Maximum percentage of AMT operating loss carryforwards usage on current year taxable income							90.00%
Company's statutory tax rate							35.00%	35.00%	35.00%
AMT rate							20.00%
Alternate minimum tax credit carryforward amount	$ 200,000						$ 200,000