Income Taxes - Income (Loss) Before Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Taxes [Line Items]
Total income before income taxes	$ (6,630)	$ (16,462)	$ (26,846)	$ (34,805)
Ireland
Income Taxes [Line Items]
Total income before income taxes	(14,302)	(18,314)	(36,625)	(34,203)
United States
Income Taxes [Line Items]
Total income before income taxes	5,952	1,773	12,309	(1,043)
France
Income Taxes [Line Items]
Total income before income taxes	$ 1,720	$ 79	$ (2,530)	$ 441