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Related Party Transactions (Details) - USD ($) shares in Millions, $ in Millions				12 Months Ended
	May 03, 2021	Dec. 14, 2020	Dec. 04, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	May 04, 2021	May 02, 2021	Jul. 01, 2020	Jun. 30, 2020
Fiserv \| New Omaha
Related Party Transaction [Line Items]
Secondary public offering (in shares)	23.0	20.1
New Omaha
Related Party Transaction [Line Items]
Number of shares to be repurchased (in shares)	5.0	1.8
Share repurchase amount	$ 588		$ 200
New Omaha \| Fiserv
Related Party Transaction [Line Items]
Ownership percentage by noncontrolling owner		13.00%			16.00%		9.00%	13.00%
Merchant Alliances
Related Party Transaction [Line Items]
Amounts due from unconsolidated merchant alliances				$ 36	$ 37
Merchant Alliances \| Related Party Fees
Related Party Transaction [Line Items]
Processing, administrative service, and other fees				203	236	$ 112
Merchant Alliances \| Related Party Fees \| Merchant Alliances
Related Party Transaction [Line Items]
Processing, administrative service, and other fees				171	183	76
Corporate joint venture \| Banc of America Merchant Services
Related Party Transaction [Line Items]
Percentage of interest in joint venture									51.00%	51.00%
Affiliated Entity \| Related Party Fees \| Lending Solutions Business And Investment Services Business
Related Party Transaction [Line Items]
Processing, administrative service, and other fees				$ 37	$ 58	$ 36