Convertible Preferred Stock, Net - Preferred Stock Activity (Details) - Contingent Convertible Preferred Stock - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Dollar Value
Beginning balance	$ 77,392	$ 77,546
Conversion to common stock	(284)	(161)
Allocation of issuance costs	12	7
Ending balance	$ 77,120	$ 77,392
Share Count
Beginning balance, shares (in shares)	801,606	803,200
Conversion to common stock (in shares)	(2,818)	(1,594)
Ending balance, shares (in shares)	798,788	801,606