Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Tax Disclosure [Abstract]
Federal and state income tax expense	$ 600,000	$ 300,000	$ 1,000,000	$ 600,000
Unrecognized tax benefits	0	$ 0	0	0
Interest or penalties related to uncertain tax positions			0	$ 0
Current tax liability	100,000		100,000
Deferred tax liability	$ 1,200,000		$ 1,200,000
Tax years open to examination			2011-2014