Financial Instruments Financial Instruments (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022
Cash Equivalents [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity securities	$ 1,619	$ 2,296	$ 921
Marketable Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity securities	$ 108	124	119
Other Assets [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity securities		$ 27	$ 24