Leases (Summary of Financial Information Associated with Leases) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Assets
Operating lease right-of-use assets	$ 784	$ 688
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued expenses and other liabilities	Accrued expenses and other liabilities
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Short-term debt and current maturities of long-term debt	Short-term debt and current maturities of long-term debt
Total leased assets	$ 1,023	$ 913
Current
Accrued expenses and other liabilities	202	178
Short-term debt and current maturities of long-term debt	53	60
Long-term
Operating lease liabilities	$ 621	$ 549
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Long-term debt	Long-term debt
Long-term debt	$ 82	$ 75
Total lease liabilities	958	862
Property and equipment, net
Assets
Accumulated depreciation	(19)	(11)
Finance lease, right-of-use asset	12	16
Sales of rental equipment
Assets
Finance lease, right-of-use asset, before accumulated amortization	329	295
Accumulated depreciation	(102)	(86)
Finance lease, right-of-use asset	227	209
Non-rental vehicles
Assets
Finance lease, right-of-use asset, before accumulated amortization	8	8
Buildings
Assets
Finance lease, right-of-use asset, before accumulated amortization	$ 23	$ 19