Shareholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Aug. 31, 2015	May. 31, 2008
Stockholders Equity Note [Abstract]
Common stock shares authorized for repurchase			2,000,000	2,000,000
Shares remain authorized for repurchase	1,592,026
Common stock repurchased, Shares	2,407,974	0
Aggregate purchase price	$ 63,953
Average price per repurchased shares	$ 26.56