Leases (Lease Balances) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
ROU assets recorded during the period associated with:
Finance leases	$ 406.6		$ 426.0
Operating leases	1,211.1		1,327.8
Total ROU assets	1,617.7		1,753.8
Lease liabilities:
Finance lease	461.3		484.0
Operating leases	1,236.5		1,364.8
Total lease liabilities	$ 1,697.8		$ 1,848.8
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Property and equipment, net		Property and equipment, net
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other assets, net		Other assets, net
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Long-term debt and finance lease obligations		Long-term debt and finance lease obligations
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	Current portion of debt and finance lease obligations (notes 9 and 10)		Current portion of debt and finance lease obligations (notes 9 and 10)
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Other Accrued Liabilities, Current		Other Accrued Liabilities, Current
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other Liabilities, Noncurrent		Other Liabilities, Noncurrent
Weighted average remaining lease term for finance leases	22 years 3 months 18 days
Weighted average discount rate, for finance leases	6.00%
ROU assets associated with finance leases	$ 8.7	$ 9.6
Weighted average remaining lease term for operating leases	12 years 9 months 18 days
Weighted average discount rate, for operating leases	5.90%
Addition to ROU assets associated with operating leases	$ 51.2	$ 32.9