Fair Value of Financial Information - Unrealized Positions for Available-for-sale Fixed-Income Securities (Details) - Available-for-sale fixed-income securities - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost Basis	$ 3	$ 36
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	1
Fair Value	$ 3	$ 35

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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+ Details

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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+ Details