Income Taxes - Loss Before Tax (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Domestic	$ (16,658)	$ (19,925)	$ (4,153)
Foreign	27	33	8
Total loss before income taxes	$ (16,631)	$ (19,892)	$ (4,145)