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Debt and Credit Agreements - Narrative (Details) | 3 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Dec. 31, 2023 USD ($) swap | Sep. 30, 2023 USD ($) | Jun. 30, 2023 USD ($) | Dec. 31, 2022 USD ($) | Mar. 31, 2022 USD ($) swap | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Sep. 07, 2023 USD ($) | Jul. 28, 2022 USD ($) | Jul. 01, 2021 USD ($) | Dec. 31, 2020 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Notional Value of Hedged Notes |  |  |  |  |  |  |  | $ 0 |  |  |  |
Other Operating Activities |  |  |  |  |  | $ (5,000,000) | $ (17,000,000) | $ 12,000,000 |  |  |  |
Quality Carriers, Inc. |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Finance lease obligations and debt assumed |  |  |  |  |  |  |  |  |  |  | $ 68,000,000 |
Interest Rate Swap | Cash Flow Hedging | Designated as Hedging Instrument |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Interest rate fair value hedge asset at fair value | $ 48,000,000 |  |  | $ 127,000,000 |  | 48,000,000 | 127,000,000 |  |  |  |  |
Derivative asset, notional value | 114,000,000 |  |  | 340,000,000 |  | 114,000,000 | 340,000,000 |  |  |  |  | $ 500,000,000
Cash flow hedge derivative instrument assets at fair value | $ 48,000,000 |  |  | 127,000,000 |  | 48,000,000 | 127,000,000 |  |  |  |  |
Notional amount settled |  | $ 113,000,000 | $ 113,000,000 | 160,000,000 |  |  |  |  |  |  |  |
Derivative, cash received on hedge |  |  |  | 52,000,000 |  |  |  |  |  |  |  |
Other Operating Activities |  | $ 51,000,000 | $ 44,000,000 |  |  |  |  |  |  |  |  |
2023 Fixed-to-Floating Interest Rate Swaps | Fair Value Hedging |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative, number of fair value hedges | swap | 2 |  |  |  |  |  |  |  |  |  |  |
Derivative, term of contract | 10 years |  |  |  |  |  |  |  |  |  |  |
2023 Fixed-to-Floating Interest Rate Swaps | Fair Value Hedging | Designated as Hedging Instrument |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Interest rate fair value hedge asset at fair value | $ 19,000,000 |  |  |  |  | 19,000,000 |  |  |  |  |  |
2022 Fixed-to-Floating Interest Rate Swap | Fair Value Hedging |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative, number of fair value hedges | swap |  |  |  |  | 5 |  |  |  |  |  |  |
Derivative, term of contract |  |  |  |  | 10 years |  |  |  |  |  |  |
2022 Fixed-to-Floating Interest Rate Swap | Fair Value Hedging | Designated as Hedging Instrument |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Interest rate fair value hedge liability at fair value | 107,000,000 |  |  | 118,000,000 |  | 107,000,000 | 118,000,000 |  |  |  |  |
Commercial Paper |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Line of credit facility capacity | 1,000,000,000 |  |  |  |  | 1,000,000,000 |  |  |  |  |  |
Line of credit amount outstanding | 0 |  |  |  |  | 0 |  |  |  |  |  |
3.25% Notes Due 2027 |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Notional Value of Hedged Notes | $ 850,000,000 |  |  |  |  | $ 850,000,000 |  |  |  |  |  |
Interest rate | 3.25% |  |  |  |  | 3.25% |  |  |  |  |  |
Unsecured Revolving Credit Facility Expiring March 2024 | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Line of credit facility capacity |  |  |  | 1,200,000,000 |  |  | 1,200,000,000 |  |  |  |  |
Line of credit facility, amount outstanding | $ 0 |  |  |  |  | $ 0 |  |  |  |  |  |
4.1% Notes Due 2032 |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Notional Value of Hedged Notes |  |  |  |  |  |  |  |  |  | $ 950,000,000 |  |
Interest rate |  |  |  |  |  |  |  |  |  | 4.10% |  |
4.5% Notes Due 2052 |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Notional Value of Hedged Notes |  |  |  |  |  |  |  |  |  | $ 900,000,000 |  |
Interest rate |  |  |  |  |  |  |  |  |  | 4.50% |  |
4.65% Notes Due 2068 |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Notional Value of Hedged Notes |  |  |  |  |  |  |  |  |  | $ 150,000,000 |  |
Interest rate |  |  |  |  |  |  |  |  |  | 4.65% |  |
Fixed Rate Notes Due Between 2036 and 2040 |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Notional Value of Hedged Notes | 1,050,000,000 |  |  | $ 800,000,000 | $ 800,000,000 | 1,050,000,000 | $ 800,000,000 |  |  |  |  |
Fixed Rate Notes Due 2033 |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Notional Value of Hedged Notes | 250,000,000 |  |  |  |  | 250,000,000 |  |  |  |  |  |
5.2% Notes Due 2033 |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Notional Value of Hedged Notes |  |  |  |  |  |  |  |  | $ 600,000,000 |  |  |
Interest rate |  |  |  |  |  |  |  |  | 5.20% |  |  |
Unsecured Revolving Credit Facility Due 2028 | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Line of credit facility capacity | $ 1,200,000,000 |  |  |  |  | $ 1,200,000,000 |  |  |  |  |  |

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