Leases (Presentation on Consolidated Balance Sheet) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Sep. 30, 2020
Leases [Abstract]
Operating lease ROU asset, other noncurrent assets	$ 566.2	$ 376.8
Operating lease liabilities, payables and accrued liabilities	78.6	70.7
Operating lease liabilities, noncurrent	503.4	335.8
Total operating lease liabilities	$ 582.0	$ 406.5
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other noncurrent assets	Other noncurrent assets
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accounts Payable and Accrued Liabilities, Current	Accounts Payable and Accrued Liabilities, Current
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other noncurrent liabilities	Other noncurrent liabilities