Stock-Based Compensation and Employee Benefit Plans - Stock Option and Restricted Stock Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Outstanding Options/RSUs, Number of Shares
Outstanding (in shares)	17,837,316
Exercised (in shares)	(110,949)
Cancelled (in shares)	(219,729)
Outstanding (in shares)	17,506,638	17,837,316
Outstanding Options Weighted Average Exercise Price
Outstanding (in dollars per share)	$ 20.76
Exercised (in dollars per share)	6.14
Cancelled (in dollars per share)	25.79
Outstanding (in dollars per share)	$ 20.79	$ 20.76
Outstanding, remaining contractual life	6 years 7 months 28 days	6 years 11 months 9 days
Outstanding, aggregate intrinsic value	$ 6,814	$ 14,964
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Vested and expected to vest (in shares)	16,856,937
Exercisable (in shares)	9,499,310
Vested and expected to vest, weighted average exercise price (in dollars per share)	$ 21.20
Exercisable, weighted average exercise price (in dollars per share)	$ 28.59
Vested and expected to vest, remaining contractual life	6 years 6 months 26 days
Exercisable, remaining contractual life	4 years 9 months 4 days
Vested and expected to vest, aggregate intrinsic value	$ 6,071
Exercisable, aggregate intrinsic value	$ 9