Discontinued Operations - Schedule of Major Components of Discontinued Operations, Net of Tax (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
Jan. 31, 2024	Mar. 31, 2024	Mar. 31, 2023
Major components of earnings (loss) from discontinued operations before income taxes:
Earnings (loss) from discontinued operations, net of tax attributable to FIS		$ 707	$ 45
Worldpay Merchant Solutions \| Discontinued Operations, Held-for-Sale
Major components of earnings (loss) from discontinued operations before income taxes:
Revenue	$ 403		1,113
Cost of revenue	(63)		(600)
Selling, general, and administrative expenses	(155)		(487)
Interest income (expense), net	1		5
Other, net	(4)		24
Earnings (loss) from discontinued operations related to major components of pretax earnings (loss)	182		55
Loss on sale of disposal group	(466)	$ (466)	0
Earnings (loss) from discontinued operations	(284)		55
Provision (benefit) for income taxes	(991)		11
Earnings (loss) from discontinued operations, net of tax attributable to FIS	$ 707		$ 44

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