Long-term Debt - Interest Expense, Net (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Debt Disclosure [Abstract]
Interest expense	$ (136.6)	$ (130.4)
Interest income	0.2	0.2
Capitalized interest	0.7	0.4
Interest expense, net	(135.7)	$ (129.8)
Coupon interest	2.3
Amortization of debt discount	3.1
Amortization of debt issuance costs	0.2
Convertible Notes interest expense	$ 5.6