Debt - Schedule of Short-term Debt (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Short-term Debt
Total Short-term borrowings	$ 636	$ 4,760
Senior Commercial Paper Notes
Short-term Debt
Commercial paper	$ 4,500
Senior Commercial Paper Notes \| FIS Credit Agreement \| ECP Notes
Short-term Debt
Short term debt, weighted average interest rate	3.10%
Maturities	183 days
Commercial paper	$ 104	2,118
Senior Commercial Paper Notes \| FIS Credit Agreement \| USCP Notes
Short-term Debt
Short term debt, weighted average interest rate	4.60%
Maturities	397 days
Commercial paper	$ 532	$ 2,642

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Weighted average interest rate of short-term debt outstanding calculated at point in time.

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