Debt - Short-Term Debt (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2021	Dec. 31, 2020
Short-term Debt
Other	$ 5	$ 144
Total Short-term borrowings	$ 2,873	2,750
Euro-commercial paper notes ("ECP Notes") \| Commercial paper \| FIS credit agreements
Short-term Debt
Short term debt, weighted average interest rate	(0.50%)
Maturities	183 days
Commercial paper	$ 439	861
U.S. commercial paper notes ("USCP Notes") \| Commercial paper \| FIS credit agreements
Short-term Debt
Short term debt, weighted average interest rate	(0.30%)
Maturities	397 days
Commercial paper	$ 2,429	$ 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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