Stockholders' Equity - Statement of Stockholders' Equity (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2019
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance (in shares)			49,447,473
Beginning Balance	$ 1,065,757	$ 1,392,708	$ 1,118,829	$ 1,383,717
Stock-based compensation plans	8,894	11,037	11,391	16,215
Net income (loss)	(55,318)	(87,993)	(85,016)	(50,410)
Other comprehensive income	$ 21,137	17,434	$ (4,734)	(15,697)
Ending Balance (in shares)	49,522,582		49,522,582
Ending Balance	$ 1,040,470	$ 1,333,186	$ 1,040,470	1,333,186	$ 1,383,717
Accounting Standards Update [Extensible Enumeration]					us-gaap:AccountingStandardsUpdate201613Member
Cumulative Effect, Period of Adoption, Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance				$ (639)
Ending Balance					$ (639)
Ordinary Shares
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance (in shares)	49,455,000	49,414,000	49,447,000	49,411,000
Beginning Balance	$ 76,310	$ 76,259	$ 76,300	$ 76,257
Stock-based compensation plans (in shares)	68,000	62,000	76,000	65,000
Stock-based compensation plans	$ 95	$ 79	$ 105	$ 81
Ending Balance (in shares)	49,523,000	49,476,000	49,523,000	49,476,000	49,411,000
Ending Balance	$ 76,405	$ 76,338	$ 76,405	$ 76,338	$ 76,257
Additional Paid-In Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	1,770,407	1,739,873	1,768,156	1,734,870
Stock-based compensation plans	8,706	10,925	10,957	15,928
Ending Balance	1,779,113	1,750,798	1,779,113	1,750,798	1,734,870
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	(798)	(1,090)	(1,034)	(1,263)
Stock-based compensation plans	93	33	329	206
Ending Balance	(705)	(1,057)	(705)	(1,057)	(1,263)
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	1,938	(52,523)	27,809	(19,392)
Other comprehensive income	21,137	17,434	(4,734)	(15,697)
Ending Balance	23,075	(35,089)	23,075	(35,089)	(19,392)
Accumulated Deficit
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	(782,100)	(369,811)	(752,402)	(406,755)
Net income (loss)		(87,993)		(50,410)
Ending Balance	$ (837,418)	$ (457,804)	$ (837,418)	(457,804)	(406,755)
Accumulated Deficit | Cumulative Effect, Period of Adoption, Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance				$ (639)
Ending Balance					$ (639)