Fair Value of Financial Instruments - Schedule of Fair Value Option (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fixed maturity securities, at fair value under fair value option	$ 94	$ 0
Other long-term investments, Fair value	264	248
Other loans, within other long-term investments, Aggregate unpaid principal	267	250
Loan receivable, within prepaid expenses and other assets, Fair value	0	24
Loan receivable, within prepaid expenses and other assets, Aggregate unpaid principal	0	24
Fair value, option, loans held as assets, 90 days or more past due	3	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	267	270
Investments in unconsolidated affiliates
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investments in unconsolidated affiliates	267	270
Investments in unconsolidated affiliates \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investments in unconsolidated affiliates	$ 267	$ 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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Other Loans Within Other Long-term Investments, Fair Value

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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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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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