Other Financial Information - Other Current Assets (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Prepaid Expenses and Other Current Assets [Abstract]
Prepaid expenses	$ 417	$ 395
Income tax receivable	21	273
Materials, supplies and inventory	184	209
Contract assets	15	19
Assets held for sale	107	104
Other	21	14
Total other current assets	971	1,223
Acquisition Costs
Prepaid Expenses and Other Current Assets [Abstract]
Contract costs	104	107
Fulfillment Costs
Prepaid Expenses and Other Current Assets [Abstract]
Contract costs	$ 102	$ 102