Share-Based Compensation - Narrative (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($) shares	Sep. 30, 2021 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares) \| shares	0	130,565
Aggregate fair value of options granted	$ 0.0	$ 1.0
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted (in shares) \| shares	14,733	4,007,085
Aggregate fair value of units granted	$ 0.2	$ 64.1
Unrecognized stock-based compensation expense	43.0	$ 43.0
Weighted-average vesting period of unrecognized stock-based compensation expense		3 years 3 months 18 days
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense	$ 0.7	$ 0.7
Weighted-average vesting period of unrecognized stock-based compensation expense		3 years 3 months 18 days
Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares reserved under equity incentive plan (in shares) \| shares	13,400,000	13,400,000

Aggregate number of common shares reserved for future issuance.

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