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Stock-Based Compensation - Employee Stock Purchase Plan (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from shares issued in connection with employee stock purchase plan	$ 4,922,000	$ 3,216,000	$ 0
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 88,478
Unrecognized compensation expense, period for recognition (years)	14 days
Class A Common Stock \| Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period (in shares)	188,390
Shares issued during period, weighted average price per share (in dollars per share)	$ 26.13
Proceeds from shares issued in connection with employee stock purchase plan	$ 4,900,000