Debt Investments (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Proceeds from sales of available-for-sale securities	$ 146	$ 113
Gross realized gains	8	12
Available-for-sale Securities, Gross Realized Losses	(9)	(13)
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	78
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value	76
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	894
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	814
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	550
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	479
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	512
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	419
Debt Securities, Available-for-sale, Amortized Cost	2,034		$ 2,028
Debt Securities, Available-for-sale	1,788		1,747
Equity Securities, Net Unrealized Gain (Loss)	8	$ 3
Equity Securities, FV-NI, Current	18		10
Equity Securities without Readily Determinable Fair Value, Amount	$ 178		$ 186

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