Stock-Based Compensation and Employee Benefit Plans - Employee Stock Purchase Plan (Details) - 2018 ESPP - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares authorized	1,494,819
Employee stock purchase plan, compensation expense	$ 2.9	$ 2.8
Shares issued in period	992,846
Number of common stock reserved for issuance (in shares)	3,532,380