Restructuring and Severance - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Restructuring Cost And Reserve [Line Items]
Restructuring and severance	$ 215	$ 1,825	$ 408	$ 2,874
General and Administrative Expense
Restructuring Cost And Reserve [Line Items]
Severance costs			$ 100