Stockholders' Equity - Schedule of Additional Information Regarding Stock Appreciation Rights (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of stock appreciation rights vested (based on remeasurement-date fair value)	$ 14,100	$ 7,000	$ 11,800
Stock appreciation rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of stock appreciation rights exercised	3,034	7,024	1,090
Fair value of stock appreciation rights vested (based on remeasurement-date fair value)	$ 5,730	$ 6,834	$ 9,955