Fair Value of Financial Information - Carrying Amounts and Fair Values of Financial Instruments (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred stock with mandatory redemption requirements, carrying amount	$ 3	$ 3
Long-term debt, carrying amount	13,432	13,155
Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred stock with mandatory redemption requirements, fair value	3	3
Long-term debt, fair value	12,287	11,873
Fair Value \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred stock with mandatory redemption requirements, fair value	0	0
Long-term debt, fair value	10,570	10,165
Fair Value \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred stock with mandatory redemption requirements, fair value	0	0
Long-term debt, fair value	1,053	1,050
Fair Value \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred stock with mandatory redemption requirements, fair value	3	3
Long-term debt, fair value	$ 664	$ 658

Preferred Stocks With Mandatory Redemption Requirements Carrying Amount

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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- Definition

Fair value portion of shares that an entity is required to redeem for cash or other assets at a fixed or determinable date or upon the occurrence of an event.

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