Short-term and Long-term Investments, Restricted Deposits - Narrative (Details) $ in Millions	9 Months Ended
Sep. 30, 2026 USD ($) position	Dec. 31, 2025 USD ($)
Schedule of Investments and Restricted Deposits by Type [Line Items]
Accrued interest income \| $	$ 171	$ 180
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Other Assets, Current	Other Assets, Current
Positions from which gross unrealized losses were generated	5,281
Total investment positions	5,851
Commercial mortgage-backed securities
Schedule of Investments and Restricted Deposits by Type [Line Items]
Investments recorded at fair value that carry rating of AA Plus, weighted average (in years)	3 years
Rated Securities \| External Credit Rating, Investment Grade \| Investment Securities
Schedule of Investments and Restricted Deposits by Type [Line Items]
Percentage of investments in rated securities carry an investment grade rating by nationally recognized statistical rating organizations	99.00%

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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