Net Loss per Share - Reconciliation (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Numerator:
Net loss attributable to common stockholders - basic	$ (297.8)	$ (241.3)	$ (122.3)
Net loss attributable to common stockholders - diluted	$ (297.8)	$ (241.3)	$ (122.3)
Denominator:
Weighted average common shares outstanding - basic (in shares)	64,921,524	61,224,433	33,654,828
Weighted average common shares outstanding - diluted (in shares)	64,921,524	61,224,433	33,654,828
Net loss per share attributable to common stockholders - basic (usd per share)	$ (4.59)	$ (3.94)	$ (3.63)
Net loss per share attributable to common stockholders - diluted (usd per share)	$ (4.59)	$ (3.94)	$ (3.63)