Basis of Presentation (Schedule of Cash Activity) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash and cash equivalents	$ 572	$ 570	$ 581
Program cash	146	70	139
Restricted cash	3		1
Total cash and cash equivalents, program and restricted cash	$ 721	$ 642	$ 721	$ 626