Property Plant and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Jan. 01, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	$ 61,600		$ 61,600			$ 73,401
Accumulated depreciation	92,978		92,978			82,695
Depreciation and amortization expense	7,100	$ 6,200	13,000	$ 12,400
Reduction in finance lease obligations	(10,381)		(10,381)
Assets Under Finance Lease Obligations
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	21,600		21,600			26,200
Accumulated depreciation	$ 23,700		$ 23,700			$ 22,200
ASU 2016-02 adoption
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net					$ (6,100)
Accrued expenses and other current liabilities | ASU 2016-02 adoption
Property, Plant and Equipment [Line Items]
Reduction in finance lease obligations					$ 6,600