Fair Value of Financial Information - Additional Information (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Disposal Group, Including Discontinued Operations [Line Items]
Long-term restricted funds	$ 18	$ 20
Fixed-income securities
Disposal Group, Including Discontinued Operations [Line Items]
Debt securities, available-for-sale fair value	$ 0	35
Debt securities, available-for-sale, amortized cost		36
Debt securities, available-for-sale, accumulated gross unrealized loss		1
Carrying Amount
Disposal Group, Including Discontinued Operations [Line Items]
Secured seller promissory note from the sale of the Homeowner Services Group		795
Disposal Group, Disposed of by Sale \| Homeowner Services Group \| Level 3 \| Fair Value
Disposal Group, Including Discontinued Operations [Line Items]
Secured seller promissory note from the sale of the Homeowner Services Group		$ 798

Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on 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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