Fair Value of Financial Instruments - Schedule of Fair Value Option (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fixed maturity securities, at fair value under fair value option	$ 93	$ 0
Other long-term investments, Fair Value	246	248
Other loans, within other long-term investments, Aggregate unpaid principal	249	250
Loan receivable, within prepaid expenses and other assets, Fair Value	24	24
Loan receivable, within prepaid expenses and other assets, Aggregate unpaid principal	24	24
Fair value, option, loans held as assets, 90 days or more past due	4	0
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fixed maturity securities, at fair value under fair value option	0
Investments in unconsolidated affiliates	260	270
Investments in unconsolidated affiliates
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investments in unconsolidated affiliates	260	270
Investments in unconsolidated affiliates \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investments in unconsolidated affiliates	$ 260	$ 270

Loan Receivable, Within Prepaid Expenses And Other Assets, Aggregate Unpaid Principal

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Loan Receivable, Within Prepaid Expenses And Other Assets, Fair Value

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Other Loans Within Other Long-term Investments, Aggregate Unpaid Principal

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Fair value portion of investments accounted under the equity method.

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This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected.

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