Segment Information - Schedule of Acquisition, Integration and Other Costs (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Segment Reporting Information
Acquisition and integration	$ 33	$ 22	$ 84	$ 70
Total	197	137	503	481
One-Time Performance-Related Awards
Segment Reporting Information
Incremental stock compensation directly attributable to specific programs	3	20	27	46
Worldpay Merchant Solutions
Segment Reporting Information
Separation of the Worldpay Merchant Solutions business	11	9	53	119
Enterprise Costs Control and Other Initiatives
Segment Reporting Information
Other, including divestiture-related expenses and enterprise cost control and other initiatives	5	3	32	7
Platform Initiatives \| Enterprise Cost Control Initiatives and Changes in Senior Management
Segment Reporting Information
Severance and other termination expenses	99	7	205	34
Severance Cash Payments	64		142
Future Forward \| Platform Modernization
Segment Reporting Information
Enterprise transformation, including Future Forward and platform modernization	$ 46	$ 76	$ 102	$ 205

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Amount of expense for integration-related cost incurred in connection with business combination. Includes system integration and conversion costs; severance and other employee-related costs; restructuring and other post-combination costs. Excludes acquisition-related cost incurred to effect business combination; cost to issue debt or equity securities; and cost related to acquisition of asset.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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