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Investments (Details) - USD ($) $ in Millions	12 Months Ended
Investments (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Investments
Fair Value	$ 973	$ 1,086
Long term investments	207	185
Unrealized gains (losses) on trading securities	39	(129)	$ 12
Morocco
Investments
Long term investments	11
Denominated in foreign currencies
Investments
Fair Value	18	16
Domestic equity securities
Investments
Fair Value	143	433
Foreign equity securities
Investments
Fair Value	96	169
Domestic debt securities
Investments
Fair Value	593	399
Foreign debt securities
Investments
Fair Value	120	66
Money market funds held in trading accounts
Investments
Fair Value	17	12
Other trading investments
Investments
Fair Value	$ 4	$ 7