Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue:
Revenue		$ 16,226	$ 14,852	$ 10,187
Expenses:
Selling, general and administrative		5,810	5,652	3,284
Gain on sale of businesses	[1]	0	(464)	(15)
Total expenses		13,938	13,000	8,578
Operating income		2,288	1,852	1,609
Interest expense, net		(693)	(709)	(473)
Debt financing activities		0	0	(47)
Other income (expense)		71	28	(6)
Income before income taxes and income from investments in unconsolidated affiliates		1,666	1,171	1,083
Income tax provision		(363)	(196)	(198)
Net pre-tax gain	[1]	100	0	29
Net income	[1]	1,403	975	914
Less: net income attributable to noncontrolling interests and redeemable noncontrolling interests		69	17	21
Net income attributable to Fiserv, Inc.		$ 1,334	$ 958	$ 893
Net income attributable to Fiserv, Inc. per share – basic (in dollars per share)		$ 2.01	$ 1.42	$ 1.74
Net income attributable to Fiserv, Inc. per share – diluted (in dollars per share)		$ 1.99	$ 1.40	$ 1.71
Shares used in computing net income attributable to Fiserv, Inc. per share:
Basic (in shares)		662.6	672.1	512.3
Diluted (in shares)		671.6	683.4	522.6
Processing and services
Revenue:
Revenue	[2]	$ 13,307	$ 12,215	$ 8,573
Expenses:
Cost of goods and services sold		6,084	5,841	4,016
Product
Revenue:
Revenue		2,919	2,637	1,614
Expenses:
Cost of goods and services sold		$ 2,044	$ 1,971	$ 1,293

[1] The company revised the consolidated statements of cash flows presentation to include cash and cash equivalents within settlement assets as a component of total cash and cash equivalents. The company revised the 2020 and 2019 presentation for comparable purposes. Additional information is included in Note 1.

[2] Includes processing and other fees charged to related party investments accounted for under the equity method of $203 million, $236 million and $112 million for the years ended December 31, 2021, 2020 and 2019, respectively (see Note 20).