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Share-Based Compensation - Narrative (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Jun. 30, 2019	May 05, 2019	Apr. 29, 2018	Jun. 13, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		$ 7.2	$ 3.3
Subsequent Event \| Restricted Stock Units (RSUs) \| Awards Vested Upon Consummation of the IPO
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)	2,711,689
Subsequent Event \| Restricted Stock Units (RSUs) \| Awards Vested Within One Year of Consummation of the IPO
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)	362,629
Award vesting period	1 year
Subsequent Event \| Restricted Stock Units (RSUs) \| Awards Vested on Time-Vesting Conditions and Share Price Hurdles
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)	21,693,634
Class A \| Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	7,096,913
2019 Omnibus Incentive Plan \| Class A \| Subsequent Event \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares allowed for issuance (in shares)				31,864,865