Restructuring - Summary of Restructuring Activity (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Restructuring Cost And Reserve [Line Items]
Balance, beginning of period			$ 2,547
Additions, charged to restructuring expenses	$ 8,664	$ 5,818	11,809	$ 12,898
Cash payments			(5,527)
Non-cash utilization			(2,037)
Reclassification to lease liability			(193)
Balance, end of period	6,599		6,599
Employee Separation Costs
Restructuring Cost And Reserve [Line Items]
Balance, beginning of period			2,079
Additions, charged to restructuring expenses		$ 3,303	8,177	$ 5,040
Cash payments			(4,069)
Balance, end of period	6,187		6,187
Accelerated Depreciation and Impairment
Restructuring Cost And Reserve [Line Items]
Additions, charged to restructuring expenses			2,037
Non-cash utilization			(2,037)
Other Restructuring
Restructuring Cost And Reserve [Line Items]
Balance, beginning of period			468
Additions, charged to restructuring expenses			1,595
Cash payments			(1,458)
Reclassification to lease liability			(193)
Balance, end of period	$ 412		$ 412