Debt - Schedule of Principal Maturities of Long-Term Debt (Details) - FIS Credit Agreements $ in Millions	Mar. 31, 2025 USD ($)
Debt Instrument
2025	$ 995
2026	1,288
2027	1,604
2028	1,671
2029	699
Thereafter	4,954
Total principal payments	11,211
Other debt per the long-term debt table	(299)
Total long-term debt, including current portion	$ 10,912

Long-term Debt, Excluding Unamortized Discount (Premium)

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Long-Term Debt, Maturity, After Year Four

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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