Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Revenue		$ 3,769	$ 1,502
Selling, general and administrative		1,404	341
Gain on sale of businesses		(431)	(10)
Total expenses		3,140	1,129
Operating income		629	373
Interest expense, net		(187)	(57)
Debt financing activities		0	(59)
Other income		20	1
Income before income taxes and loss from investments in unconsolidated affiliates		462	258
Income tax provision		(79)	(31)
Loss from investments in unconsolidated affiliates		(6)	(2)
Net income		377	225
Plus: Net loss attributable to noncontrolling interests and redeemable noncontrolling interests		15	0
Net income attributable to Fiserv, Inc.		$ 392	$ 225
Net income attributable to Fiserv, Inc. per share – basic (in dollars per share)		$ 0.58	$ 0.58
Net income attributable to Fiserv, Inc. per share – diluted (in dollars per share)		$ 0.57	$ 0.56
Shares used in computing net income attributable to Fiserv, Inc. per share:
Basic (in shares)		678.1	391.7
Diluted (in shares)		691.2	399.1
Related Party Fees | Equity investments
Shares used in computing net income attributable to Fiserv, Inc. per share:
Processing, administrative, and other fees		$ 57	$ 9
Processing and services
Revenue	[1]	3,075	1,293
Cost of goods sold and services		1,635	624
Product
Revenue		694	209
Cost of goods sold and services		$ 532	$ 174

[1] Includes processing and other fees charged to related party investments accounted for under the equity method of $57 million and $9 million for the three months ended March 31, 2020 and 2019, respectively (see Note 21).