Income Taxes - Schedule of Reconciliation of Theoretical Tax Expense and Actual Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Loss before taxes, as reported in the consolidated statements of operations	$ (85,898)	$ (76,376)	$ (28,165)
Statutory tax rate	21.00%	21.00%	21.00%
Theoretical tax benefits on the above amount at the US statutory tax rate	$ (18,039)	$ (16,039)	$ (5,915)
Income tax at rate other than the U.S. statutory tax rate	4,845	(2,508)	692
Tax advances and non-deductible expenses including equity based compensation expenses	934	(115)	(7,623)
Operating losses and other temporary differences for which valuation allowance was provided	22,189	22,818	15,826
State tax	(2,872)	(3,436)	(1,221)
Impact of rate change	0	401	0
Change in tax reserve for uncertain tax positions	1,489	1,247	(1,728)
Other individually immaterial income tax items	(434)	20	382
Income tax expense	$ 8,112	$ 2,388	$ 413