Investments in Debt and Equity Securities - Summary of Cost Basis And Fair Value Of The Available-For-Sale Debt Securities By Contractual Maturity (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Cost Basis
Due in one year or less	$ 770
Due after one year through five years	1,534
Due after five years through ten years	400
Due after ten years	187
Debt securities, available-for-sale, cost basis	3,638	$ 3,535
Fair Value
Due in one year or less	771
Due after one year through five years	1,536
Due after five years through ten years	399
Due after ten years	186
Debt securities	3,621	3,549
U.S. governmental agency
Cost Basis
Debt securities, available-for-sale, cost basis	584	580
Fair Value
Debt securities	570	572
Residential mortgage-backed securities
Cost Basis
Debt securities, available-for-sale, cost basis	5	2
Fair Value
Debt securities	4	1
Commercial mortgage-backed securities
Cost Basis
Debt securities, available-for-sale, cost basis	158	141
Fair Value
Debt securities	$ 155	$ 139

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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