Stockholders' Equity - Schedule of Warrants Outstanding (Details) - Warrants to purchase common stock - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2018	Dec. 31, 2019
Number of Shares
Outstanding at beginning of period (in shares)	342,610
Exercised (in shares)	(59,510)
Forfeited (in shares)	(4,300)
Outstanding at end of period (in shares)	278,800
Exercisable (in shares)	278,800
Weighted- average Exercise Price
Outstanding at beginning of period (in dollars per share)	$ 9.77
Exercised (in dollars per share)	10.00
Forfeited (in dollars per share)	10.00
Outstanding at end of period (in dollars per share)	9.72
Exercisable (in dollars per share)	$ 9.72
Weighted- average Remaining Contractual Term (years)
Outstanding	4 years 3 months 4 days	3 years 8 months 16 days
Exercisable	4 years 3 months 4 days
Aggregate Intrinsic Value
Outstanding	$ 61		$ 1,585
Exercisable	$ 61