Debt - Short-Term Debt (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Short-term Debt
Other	$ 16	$ 144
Total Short-term borrowings	$ 3,484	2,750
Commercial paper \| FIS credit agreements \| Euro-commercial paper notes ("ECP Notes")
Short-term Debt
Short term debt, weighted average interest rate	(0.50%)
Maturities	183 days
Commercial paper	$ 428	861
Commercial paper \| FIS credit agreements \| U.S. commercial paper notes ("USCP Notes")
Short-term Debt
Short term debt, weighted average interest rate	0.30%
Maturities	397 days
Commercial paper	$ 3,040	$ 1,745

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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