Income Taxes - Reconciliation of Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Loss before income taxes	$ (8,824)	$ (45,942)	$ (48,497)
U.S statutory income tax rate	21.00%	21.00%	35.00%
Notional U.S. federal income taxes at statutory rate	$ (1,853)	$ (9,648)	$ (16,974)
Non-deductible expenses	741	1,030	3,308
Foreign taxes rate differential	(4,216)	(6,000)	(7,333)
Change in valuation allowance	244,344	28,657	5,742
State income taxes	(16,679)	1,957	(9,089)
Change in excess tax benefit	(26,528)	2,088	2,203
Unamortized intangible assets	(189,410)	0	0
Research and Development Credits	(2,333)	0	0
Other	(5,673)	(326)	34,881
Unrecognized tax expense (benefit)	13	(141)	427
Total income tax provision	$ (1,594)	$ 17,617	$ 13,165
Effective tax rate	18.10%	(38.30%)	(27.10%)