Components of Accumulated Other Comprehensive Loss - Reclassification out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Product revenues	$ 569,820		$ 447,281		$ 1,098,675	$ 846,122
Interest expense	15,986		14,953		32,850	27,602
Income from continuing operations before income taxes	24,795		(11,978)		32,035	(20,452)
Income tax expense (benefit)	8,564		(2,304)		12,793	(2,986)
Net income (loss)	15,080	$ 1,565	(9,455)	$ 1,227	16,645	(8,228)
Amount Reclassified from Accumulated Other Comprehensive Loss | Cumulative Unrecognized Actuarial Losses on Pension Obligations
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Income from continuing operations before income taxes	6,136		4,863		12,211	15,413
Income tax expense (benefit)	(358)		(323)		(716)	(2,033)
Net income (loss)	5,778		4,540		11,495	13,380
Amount Reclassified from Accumulated Other Comprehensive Loss | Effective Portion of Deriviatives Designated as Hedging Instruments
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Income from continuing operations before income taxes	865		695		1,680	(26)
Income tax expense (benefit)	(253)		(263)		(498)	(187)
Net income (loss)	612		432		1,182	(213)
Amount Reclassified from Accumulated Other Comprehensive Loss | Effective Portion of Deriviatives Designated as Hedging Instruments | Foreign currency exchange forward contracts
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Discontinued Operation, Gain From Disposal Of Discontinued Operation, Before Income Tax	0		0		0	12,906
Product revenues	3		(332)		(47)	(1,736)
Amount Reclassified from Accumulated Other Comprehensive Loss | Effective Portion of Deriviatives Designated as Hedging Instruments | Cross currency interest rate swaps
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	0		295		0	600
Amount Reclassified from Accumulated Other Comprehensive Loss | Effective Portion of Deriviatives Designated as Hedging Instruments | Interest rate swaps
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	862		732		1,727	1,110
Amount Reclassified from Accumulated Other Comprehensive Loss | Actuarial losses
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Defined benefit pension income	6,007		4,757		11,955	9,837
Amount Reclassified from Accumulated Other Comprehensive Loss | Prior service costs
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Defined benefit pension income	129		106		256	213
Amount Reclassified from Accumulated Other Comprehensive Loss | Pension liability transfer - discontinued business
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Defined benefit pension income	$ 0		$ 0		$ 0	$ 5,363