Additional Financial Information (Cash and Cash Equivalents and Restricted Cash Balances) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract]
Cash and cash equivalents from continuing operations	$ 7,540	$ 3,701	$ 2,423	$ 19,223
Cash and cash equivalents from discontinued operations	0	0	0	1,946
Restricted cash in Prepaid and other current assets	1	1	1	3
Restricted cash in Other Assets	118	91	70	144
Cash and Cash Equivalents and Restricted Cash	$ 7,659	$ 3,793	$ 2,494	$ 21,316