Debt Investments (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Proceeds from sales of available-for-sale securities			$ 397	$ 449
Gross realized gains			59	40
Available-for-sale Securities, Gross Realized Losses			(18)	(42)
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	$ 63		63
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value	59		59
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	1,117		1,117
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	1,032		1,032
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	509		509
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	437		437
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	513		513
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	386		386
Debt Securities, Available-for-sale, Amortized Cost	2,202		2,202
Debt Securities, Available-for-sale	1,914		1,914
Equity Securities, Net Unrealized Gain (Loss)	(4)	$ (2)	6	$ (8)
Equity Securities, FV-NI, Current	15		15		$ 10
Equity Securities without Readily Determinable Fair Value, Amount	$ 177		$ 177		$ 186

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