Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments in unconsolidated subsidiaries, fair value	$ 405		$ 378
Asset impairments	0	$ 0
Total long-term debt	3,913		3,320
Fair Value Measured at Net Asset Value \| Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments at fair value using NAV	21		21
2.500% senior notes \| Carrying Value \| Mortgages
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total long-term debt	208		196
Non-Marketable Equity Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Capital investments	$ 148		$ 148

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

The total fair value for all investments, comprising or included in the major category, of those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments) for which the entity has intentions to sell or liquidate, but the specific assets for sale or liquidation have not been identified (for example, the entity intends to sell $10,000,000 of its investments in private equity funds, but the individual investments to be sold have not been identified).

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- Definition

Amount after accumulated amortization of finite-lived and indefinite-lived intangible assets classified as other.

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