Long-Term Debt, Other Adjustments

No definition available.

Name:	fis_LongTermDebtOtherAdjustments
Namespace Prefix:	fis_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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+ Details

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Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_LongTermDebtByCurrentAndNoncurrentAbstract
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Balance Type:	na
Period Type:	duration

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as current. Excludes lease obligation.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

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Debt - Schedule of Long-Term Debt (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2026	Mar. 01, 2026	Dec. 31, 2025
Long-Term Debt
Other	$ (292)		$ (264)
Total long-term debt, including current portion	16,948		10,353
Current portion of long-term debt	(1,516)		(1,284)
Long-term debt, excluding current portion	$ 15,432		9,069
Revolving Credit Facility
Long-Term Debt
Weighted average interest rate	4.90%
Revolving credit facility	$ 167		215
Unused commitment fee	0.20%
Revolving Credit Facility \| Maximum
Long-Term Debt
Applicable margin	1.625%
Incremental Revolving Credit Facility
Long-Term Debt
Revolving credit facility	$ 0		0
Unused commitment fee	0.20%
Incremental Revolving Credit Facility \| Maximum
Long-Term Debt
Applicable margin	1.625%
Financing arrangements for certain hardware and software
Long-Term Debt
Revolving credit facility	$ 213		116
Senior USD Floating Rate Notes
Long-Term Debt
Applicable margin	1.21%
Senior Euro Floating Rate Notes
Long-Term Debt
Applicable margin	0.85%
Senior Notes \| Senior USD Notes
Long-Term Debt
Weighted average interest rate	4.50%
Senior notes	$ 11,145		6,094
Senior Notes \| Senior USD Notes \| Minimum
Long-Term Debt
Interest rates	1.70%
Senior Notes \| Senior USD Notes \| Maximum
Long-Term Debt
Interest rates	5.60%
Senior Notes \| Senior Euro Notes
Long-Term Debt
Interest rates		1.15%
Weighted average interest rate	3.10%
Senior notes	$ 4,420		3,963
Senior Notes \| Senior Euro Notes \| Minimum
Long-Term Debt
Interest rates	1.00%
Senior Notes \| Senior Euro Notes \| Maximum
Long-Term Debt
Interest rates	3.50%
Senior Notes \| Senior GBP Notes
Long-Term Debt
Weighted average interest rate	6.60%
Senior notes	$ 225		229
Senior Notes \| Senior GBP Notes \| Minimum
Long-Term Debt
Interest rates	2.30%
Senior Notes \| Senior GBP Notes \| Maximum
Long-Term Debt
Interest rates	3.40%
Senior Notes \| Senior USD Floating Rate Notes
Long-Term Debt
Senior notes	$ 500		0
Senior Notes \| Senior Euro Floating Rate Notes
Long-Term Debt
Senior notes	$ 570		$ 0