Restructuring - Restructuring and Related Costs (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring expense		$ 8,818	$ 0	$ 0
Restructuring Reserve [Roll Forward]
Ending balance of total accrued restructuring	$ 1,398	1,398
Melksham employee severance costs
Restructuring Cost and Reserve [Line Items]
Restructuring expense		5,308
Restructuring Reserve [Roll Forward]
Beginning balance of accrued restructuring		0
Additional restructuring accrual		6,630
Payments for restructuring		(5,368)
Ending balance of total accrued restructuring			$ 0
Asset write-downs & other costs
Restructuring Cost and Reserve [Line Items]
Restructuring expense		2,248
Restructuring Reserve [Roll Forward]
Additional restructuring accrual		819
Payments for restructuring		(683)
Asian operations employee severance costs
Restructuring Cost and Reserve [Line Items]
Restructuring expense	$ 1,262	$ 1,262