Fair Value Measurements - Assets and Liabilities Measured on Recurring Basis (Details) - Fair Value, Recurring - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 1,110.7	$ 1,346.4
Restricted cash	119.4	119.4
Short-term investment securities	109.5	107.1
Assets held for sale	1.9	2.5
Total assets	1,341.5	1,575.4
Derivative liability	16.7	29.2
Total liabilities	16.7	29.2
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	1,110.7	1,346.4
Restricted cash	119.4	119.4
Short-term investment securities	109.5	107.1
Assets held for sale	0.0	0.0
Total assets	1,339.6	1,572.9
Derivative liability	0.0	0.0
Total liabilities	0.0	0.0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0.0	0.0
Restricted cash	0.0	0.0
Short-term investment securities	0.0	0.0
Assets held for sale	0.0	0.0
Total assets	0.0	0.0
Derivative liability	16.7	29.2
Total liabilities	16.7	29.2
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0.0	0.0
Restricted cash	0.0	0.0
Short-term investment securities	0.0	0.0
Assets held for sale	1.9	2.5
Total assets	1.9	2.5
Derivative liability	0.0	0.0
Total liabilities	$ 0.0	$ 0.0