Stockholders' Equity - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2017	Feb. 16, 2017	Oct. 22, 2015
October 2015 Stock Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Common stock repurchase program, authorized shares			3,150,000
Common stock repurchase program, termination date	Dec. 31, 2016
Number of shares repurchased by the Company	1,578,952
Value of shares repurchased by the Company	$ 53.3
February 2017 Stock Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Common stock repurchase program, authorized shares		2,960,000
Number of shares repurchased by the Company	0