Earnings Per Share - Computation of Basic and Dilutive Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								5 Months Ended	7 Months Ended	12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Jul. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Potentially dilutive shares excluded in aggregate (in shares)											26,571,778
Net income (loss)	$ 3,105	$ (18,010)	$ (5,423)	$ (6,724)	$ (3,406)	$ (3,677)	$ (5,409)	$ (3,034)	$ (16,064)	$ (10,988)	$ (27,052)	$ (15,526)	$ (27,095)
Weighted-average basic and diluted shares outstanding:
Shares issued in reverse capitalization (in shares)											21,660,638	21,660,638	21,660,638
Shares outstanding post-recapitalization (in shares)											49,033,903	0	0
Weighted-average basic and diluted shares outstanding (in shares)											33,066,165	21,660,638	21,660,638
Basic and diluted net loss per share (USD per share)	$ 0.06	$ (0.45)	$ (0.25)	$ (0.31)	$ (0.16)	$ (0.17)	$ (0.25)	$ (0.14)			$ (0.82)	$ (0.72)	$ (1.25)