Debt - Components of Interest Expense and Effective Interest Rates of Senior Convertible Notes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Cash interest expense:
Contractual coupon interest	$ 1.8	$ 2.3	$ 7.0	$ 6.7
Non-cash interest expense:
Amortization of debt issuance costs	2.0	1.4	5.5	4.3
Total interest expense recognized on senior notes	$ 3.8	$ 3.7	$ 12.5	$ 11.0
Senior Convertible Notes due 2023
Non-cash interest expense:
Effective interest rate (as percent)	1.10%	1.10%	1.10%	1.10%
Senior Convertible Notes due 2025
Non-cash interest expense:
Effective interest rate (as percent)	0.50%	0.50%	0.50%	0.50%
Senior Convertible Notes due 2028
Non-cash interest expense:
Effective interest rate (as percent)	0.70%		0.70%