Financial Instruments - Investments - Debt Securities (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Held-to-maturity, Maturity, Fair Value [Abstract]
Debt securities, amortized cost	$ 5,126	$ 21,556
Debt securities, gross unrealized gains	6	304
Debt securities, gross unrealized losses	(16)	(53)
Debt securities, fair value	5,115	21,807
Debt securities maturities, within 1 year, fair value	4,919
Debt securities maturities, over 1 to 5 years, fair value	185
Debt securities maturities, over 5 years, fair value	12
Government and agency debt - non-U.S. [Member]
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Available-for-sale debt securities, amortized cost	953	15,946
Available-for-sale debt securities, gross unrealized gain	2	297
Available-for-sale debt securities, gross unrealized loss	(14)	(48)
Available-for-sale securities, debt maturities	941	16,195
Available-for-sale Securities, Debt Maturities [Abstract]
Available-for-sale securities, debt maturities, within 1 year, fair value	817
Available-for-sale securities, debt maturities, over 1 to 5 years, fair value	124
Available-for-sale securities, debt maturities, over 5 years, fair value	0
Available-for-sale securities, debt maturities	941	16,195
Debt Securities, Held-to-maturity, Maturity [Abstract]
Held-to-maturity securities, amortized cost	4	1,542
Held-to-maturity securities, gross unrealized gains	0	0
Held-to-maturity securities, gross unrealized losses	0	0
Held-to-maturity securities, fair value	4	1,542
Debt Securities, Held-to-maturity, Maturity, Fair Value [Abstract]
Held-to-maturity securities, debt maturities, within 1 year, fair value	0
Held-to-maturity securities, debt maturities, over 1 to 5 years, fair value	4
Held-to-maturity securities, debt maturities, over 5 years, fair value	1
Government and agency - U.S. [Member]
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Available-for-sale debt securities, amortized cost	2,601	1,313
Available-for-sale debt securities, gross unrealized gain	0	0
Available-for-sale debt securities, gross unrealized loss	0	0
Available-for-sale securities, debt maturities	2,601	1,313
Available-for-sale Securities, Debt Maturities [Abstract]
Available-for-sale securities, debt maturities, within 1 year, fair value	2,601
Available-for-sale securities, debt maturities, over 1 to 5 years, fair value	0
Available-for-sale securities, debt maturities, over 5 years, fair value	0
Available-for-sale securities, debt maturities	2,601	1,313
Corporate and Other [Member]
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Available-for-sale debt securities, amortized cost	1,006	1,584
Available-for-sale debt securities, gross unrealized gain	4	7
Available-for-sale debt securities, gross unrealized loss	(2)	(4)
Available-for-sale securities, debt maturities	1,007	1,586
Available-for-sale Securities, Debt Maturities [Abstract]
Available-for-sale securities, debt maturities, within 1 year, fair value	982
Available-for-sale securities, debt maturities, over 1 to 5 years, fair value	26
Available-for-sale securities, debt maturities, over 5 years, fair value	0
Available-for-sale securities, debt maturities	1,007	1,586
Time deposits and other [Member]
Debt Securities, Held-to-maturity, Maturity [Abstract]
Held-to-maturity securities, amortized cost	561	1,171
Held-to-maturity securities, gross unrealized gains	0	0
Held-to-maturity securities, gross unrealized losses	0	0
Held-to-maturity securities, fair value	561	$ 1,171
Debt Securities, Held-to-maturity, Maturity, Fair Value [Abstract]
Held-to-maturity securities, debt maturities, within 1 year, fair value	519
Held-to-maturity securities, debt maturities, over 1 to 5 years, fair value	31
Held-to-maturity securities, debt maturities, over 5 years, fair value	$ 11

Available-for-sale Securities, Debt Maturities, After Year Five, Fair Value

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Debt Securities, Accumulated Gross Unrealized Gain

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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Amount, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) and 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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