Debt Investments (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Proceeds from sales of available-for-sale securities			$ 449	$ 339
Gross realized gains			40	41
Available-for-sale Securities, Gross Realized Losses			(42)	(8)
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	$ 71		71
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value	66		66
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	706		706
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	627		627
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	710		710
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	581		581
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	525		525
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	401		401
Debt Securities, Available-for-sale, Amortized Cost	2,012		2,012		$ 1,997
Debt Securities, Available-for-sale	1,675		1,675		2,059
Equity Securities, Net Unrealized Gain (Loss)	2	$ 6	8	$ 7
Equity Securities, FV-NI, Current	10		10		20
Equity Securities without Readily Determinable Fair Value, Amount	$ 191		$ 191		$ 209

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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