Stock Based Compensation - Stock Options, Restricted Stock and Restricted Stock Units Activity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Stock options (1)
Number of options
Balance at beginning of period (in shares)	10,865,868
Granted (in shares)	0
Forfeited (in shares)	(64,499)
Exercised (in shares)	0
Balance at end of period (in shares)	10,801,369	10,865,868
Weighted-average exercise price
Balance at beginning of period (in USD per share)	$ 19.31
Granted (in USD per share)	0
Forfeited (in USD per share)	15.89
Exercised (in USD per share)	0
Balance at end of period (in USD per share)	$ 19.33	$ 19.31
Expected to vest at end of period (in shares)	4,721,369
Exercisable at end of period (in shares)	6,080,000
Expected to vest at end of period (in USD per share)	$ 15.89
Exercisable at end of period (in USD per share)	$ 22.00
Weighted-average remaining contractual term (in years)	5 years 6 months	5 years 8 months 12 days
Weighted average remaining contractual term (in years) of options expected to vest	8 years 4 months 24 days
Weighted average remaining contractual term (in years) of options exercisable	3 years 2 months 12 days
Aggregate intrinsic value	$ 0.0	$ 0.0
Aggregate intrinsic value of options expected to vest	0.0
Aggregate intrinsic value of options exercisable	$ 0.0
Restricted stock and restricted stock units
Number of shares
Balance at beginning of period (in shares)	8,682,523
Granted (in shares)	5,290,217
Forfeited (in shares)	(68,486)
Vested (in shares)	(2,909,844)
Balance at end of period (in shares)	10,994,410	8,682,523
Weighted-average grant date fair value
Balance at beginning of period (in USD per share)	$ 13.78
Granted (in USD per share)	10.44
Forfeited (in USD per share)	13.22
Vested (in USD per share)	14.47
Balance at end of period (in USD per share)	$ 11.99	$ 13.78
Weighted-average remaining contractual term (in years)	1 year 6 months	1 year
Aggregate intrinsic value	$ 110.4	$ 101.6