Other Financial Information - Other Current Assets (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid expenses	$ 48	$ 46
Contract acquisition costs	34	38
Contract fulfillment costs	28	30
Asset, Held-for-Sale, Not Part of Disposal Group, Other	29	0
Other	5	6
Total other current assets	144	120
Other	$ 679	$ 654