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Stock Based Compensation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Stock Based Compensation
Shares reserved for future issuance	0
Stock Options Granted (in shares)	478		423
Vesting percentage on each anniversary of the grant date	25.00%
Maximum term for stock options	6 years 3 months	6 years 3 months
Stock based compensation expense	$ 2.2	$ 1.4
Grant date fair value of stock options granted	$ 6.70
Unrecognized compensation cost related to unvested stock options	$ 13.2
Unrecognized compensation cost related to unvested options, recognized weighted-average period	2 years 8 months 12 days
Class A common stock
Stock Based Compensation
Number of shares reserved	800
Class A common stock \| Omnibus Plan
Stock Based Compensation
Shares reserved for future issuance	3,914
Share available for issuance	1,299
Maximum
Stock Based Compensation
Maximum term for stock options	10 years