Income Taxes - Schedule of Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Current taxes:
Current taxes expense (benefit), United States	$ 2	$ 1	$ 144
Current taxes	1,002	292	(241)
Deferred taxes:
Deferred tax expense (benefit), United States	0	0	0
Deferred income tax expense (benefit)	0	0	0
Income tax expense (benefit)	1,002	292	(241)
Korea
Current taxes:
Current foreign tax expense (benefit)	5	0	(641)
Deferred taxes:
Deferred foreign income tax expense (benefit)	0	0	0
Other
Current taxes:
Current foreign tax expense (benefit)	995	291	256
Deferred taxes:
Deferred foreign income tax expense (benefit)	$ 0	$ 0	$ 0