Income Taxes - Loss Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
United States	$ (40,242)	$ (29,162)
Foreign	219	(190)
Net loss before noncontrolling interest	$ (40,023)	$ (29,352)