Fair Value of Financial Instruments - Schedule of Fair Value Option, Disclosures (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Fair Value Disclosures [Abstract]
Fixed maturity securities, at fair value under fair value option	$ 78		$ 78		$ 0
Investments in unconsolidated affiliates	256		256		270
Other loans, within other long-term investments, fair value	296		296		248
Other loans, within other long-term investments, Aggregate unpaid principal	299		299		250
Loan receivable, within prepaid expenses and other assets, Fair value	0		0		24
Loan receivable, within prepaid expenses and other assets, Aggregate unpaid principal	0		0		24
Fair value, option, loans held as assets, 90 days or more past due	3		3		$ 0
Fixed maturity securities, at fair value under fair value option
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other loans	12	$ 0	14	$ 0
Investments in unconsolidated affiliates
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other loans	(11)	(2)	(14)	(2)
Other loans
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other loans	$ 0	$ 0	$ (2)	$ 0

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

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Other Loans

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Fair value portion of investments accounted under the equity method.

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

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