Discontinued Operations - Schedule of Major Components of Discontinued Operations, Net of Tax (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	6 Months Ended
Jan. 31, 2024	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Major components of earnings (loss) from discontinued operations before income taxes:
Earnings (loss) from discontinued operations, net of tax attributable to FIS		$ 1	$ (6,679)	$ 709	$ (6,634)
Worldpay Merchant Solutions \| Discontinued Operations, Held-for-Sale
Major components of earnings (loss) from discontinued operations before income taxes:
Revenue		4	1,322	406	2,435
Cost of revenue		(2)	(670)	(64)	(1,270)
Selling, general, and administrative expenses		0	(479)	(155)	(965)
Asset impairments		0	(6,840)	0	(6,840)
Interest income (expense), net		0	7	1	11
Other, net		(1)	23	(4)	48
Earnings (loss) from discontinued operations related to major components of pretax earnings (loss)		1	(6,637)	184	(6,581)
Loss on sale of disposal group	$ (466)	0	0	(466)	0
Earnings (loss) from discontinued operations		1	(6,637)	(282)	(6,581)
Provision (benefit) for income taxes	$ (991)	0	43	(991)	55
Earnings (loss) from discontinued operations, net of tax attributable to FIS		$ 1	$ (6,680)	$ 709	$ (6,636)

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