Employee Benefit Plans - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Share-based Compensation
Employer matching contribution, percent of match	50.00%
Profit sharing expenses	$ 125	$ 107	$ 106
Discontinued operations	$ 0	3	29
Employee contribution of pretax annual compensation	40.00%
Employee matching contribution, percent of employees' gross pay	6.00%
Incremental stock compensation directly attributable to specific programs	$ 0	3	34
Total unrecognized compensation cost related to non-vested stock awards	$ 197	$ 222
Weighted average period over which compensation cost is expected to be recognized	1 year 6 months	1 year 6 months
Selling, General and Administrative Expenses
Share-based Compensation
Incremental stock compensation directly attributable to specific programs	$ 181	$ 186	120
FIS Plan Amended and Restated
Share-based Compensation
Shares available for grant, ending (in shares)	24,000,000
Stock Options
Share-based Compensation
Minimum percentage contribution made by employees of their salary to employee benefit plan	3.00%
Maximum percentage contribution made by employees of their salary to employee benefit plan	15.00%
Employer matching contribution, percent of match	20.00%
Profit sharing expenses	$ 10	10	11
Discontinued operations	$ 0	$ 1	$ 1
Restricted Stock Units
Share-based Compensation
Vesting period	3 years
Restricted stock, shares granted (in shares)	2,000,000	3,000,000	3,000,000
Restricted stock weighted average grant price (in dollars per share)	$ 70.03	$ 70.65	$ 61.34
Fair value of vested stock	$ 145	$ 93	$ 40
Performance Stock Units
Share-based Compensation
Restricted stock, shares granted (in shares)	1,000,000
Restricted stock weighted average grant price (in dollars per share)	$ 74.91
Granted (less than) (in shares)	1,000,000	1,000,000	1,000,000
Weighted average exercise price of awards granted (in dollars per share)	$ 74.91	$ 69.75	$ 65.43
Vested	$ 97	$ 17	$ 10

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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