Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Alternative minimum tax credit carry forward	$ 19,000	$ 18,800
Unrecognized tax benefits	0	0
Excess tax benefit from equity compensation	$ 0	$ 3,813	$ 1,380