Stock Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	May 18, 2016	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized shares of stock, option plan, maximum	1,700,000
Aggregate number of shares issued in respect of restricted stock awards	500,000
Options available for award each plan year	1,200,000
Maximum number of shares of restricted stock or shares subject to a restricted stock units award granted				50,000
Maximum number of options and SARs				100,000
Maximum number of stock options and SARs awarded				10,000
Maximum number of Shares of restricted stock or shares subject to a restricted stock units award granted to individual non-employee director				5,000
Vesting period of awards				1/3 per year
Recognition of compensation expense		$ 720	$ 756	$ 2,050	$ 2,144
Number of share available for grant for prior plans		0		0
Maximum term for awards granted (years)				10 years
Shares issued related stock option exercises				248,677	215,967
Total intrinsic value of options exercised				$ 4,670	$ 1,908
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options granted				967,285
Number of shares granted				289,637