Stock-Based Compensation and Stock Awards - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense			$ 10,477,000	$ 9,442,000
Capitalized expense	$ 0	$ 0	0	0
Selling, General and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 3,700,000	$ 3,200,000	$ 10,500,000	$ 9,400,000