Lease Obligations - Lessee - Other Information (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Leases [Abstract]
Operating leases, weighted average remaining lease term	11 years		10 years 9 months 18 days
Finance leases, weighted average remaining lease term	15 years 2 months 1 day		15 years 3 months 21 days
Operating leases, weighted average discount rate	3.66%		3.35%
Finance leases, weighted average discount rate	2.98%		2.94%
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 68	$ 67
Operating cash flows from finance leases	3	4
Financing cash flows from finance leases	12	13
Gains on sale-leaseback transactions	$ 1	$ 4

Cash Flow Activities, Leases

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- Definition

Amount of interest paid on finance lease liability.

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Amount of cash outflow for principal payment on finance lease.

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Weighted average discount rate for finance lease calculated at point in time.

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Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of gain (loss) on sale and leaseback transaction from transfer of asset accounted for as sale.

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