Debt Fair Value of Debt Instruments (Details) - USD ($) $ in Billions	Sep. 30, 2023	Dec. 31, 2022
Debt Disclosure [Abstract]
Fair value of debt excluding finance leases	$ 20.5	$ 21.5
Book value of debt excluding finance leases	$ 23.4	$ 23.3

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant