Supplemental Consolidated Financial Information - Property, Plant and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 6,132	$ 6,446
Accumulated depreciation	(4,869)	(5,203)
Property and equipment, net	1,263	1,243
Depreciation expense	370	441	$ 442
Computer equipment and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 4,685	4,905
Computer equipment and software | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	1 year
Computer equipment and software | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	4 years
Land and buildings, including building improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 810	829
Property, plant and equipment, useful life	30 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 428	418
Property, plant and equipment, useful life	5 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 133	141
Property, plant and equipment, useful life	3 years
Construction in progress and other
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 76	$ 153