Share Repurchase Program - Additional Information (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2016	Jan. 31, 2016	Jul. 31, 2014	Jan. 31, 2014
Equity [Abstract]
Shares repurchase program authorized		$ 25,000,000	$ 65,000,000	$ 35,000,000
Common stock shares repurchased	41,667
Cost of common stock shares repurchased	$ 5,400,000
Shares repurchase program expiration date	Feb. 29, 2016
Dollar value of shares that may yet be purchased under share repurchase program	$ 19,600,000