Debt (Estimated Fair Value of Significant Financial Instruments) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt	$ 2,111	$ 268
Long-term debt	10,841	11,227
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt	2,102	265
Long-term debt	$ 10,321	$ 10,544