Stockholders' Equity - Schedule of Stock Options Activity (Details) - 2015 Equity Incentive Plan - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Number of shares
Outstanding at the beginning (in shares)	3,976
Granted (in shares)	57
Exercised (in shares)	(34)
Forfeited (in shares)	(182)
Expired (in shares)	(440)
Outstanding at the end (in shares)	3,377	3,976
Expected to vest (in shares)	3,377
Exercisable (in shares)	3,045
Weighted Average Exercise Price
Outstanding at the beginning (in dollars per share)	$ 6.20
Granted (in dollars per share)	0.61
Exercised (in dollars per share)	0.86
Forfeited (in dollars per share)	5.25
Expired (in dollars per share)	5.90
Outstanding at the end (in dollars per share)	6.24	$ 6.20
Expected to vest (in dollars per share)	6.24
Exercisable (in dollars per share)	$ 6.44
Weighted Average Remaining Term
Weighted average remaining term (in years)	2 years 4 months 9 days	3 years 9 months 18 days
Vested and expected to vest (in years)	2 years 4 months 9 days
Exercisable (in years)	1 year 8 months 15 days
Aggregate Intrinsic Value
Outstanding	$ 0	$ 0
Expected to vest	0
Exercisable	$ 0