Financial Instruments Financial Instruments (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022
Cash Equivalents [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity securities	$ 780	$ 2,296	$ 1,414
Marketable Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity securities	85	124	290
Other Assets [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity securities	$ 27	$ 27	$ 53