Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Net income	$ 914	$ 1,187	$ 1,246
Other comprehensive (loss) income:
Fair market value adjustment on cash flow hedges, net of income tax (benefit) provision of ($46 million), ($2 million) and $2 million	(134)	(5)
Fair market value adjustment on cash flow hedges, net of income tax (benefit) provision of ($46 million), ($2 million) and $2 million			4
Unrealized loss on defined benefit pension plans, net of income tax benefit of $1 million	(4)	0	0
Foreign currency translation	8	(11)	12
Total other comprehensive (loss) income	(121)	(13)	22
Comprehensive income	793	1,174	1,268
Less: Net income attributable to noncontrolling interests and redeemable noncontrolling interests	21	0	0
Less: Other comprehensive loss attributable to noncontrolling interests	(8)	0	0
Comprehensive income attributable to Fiserv, Inc.	780	1,174	1,268
Cost of Services
Other comprehensive (loss) income:
Reclassification adjustment for net realized (gains) losses on cash flow hedges	(1)	(1)
Reclassification adjustment for net realized (gains) losses on cash flow hedges			0
Interest Expense
Other comprehensive (loss) income:
Reclassification adjustment for net realized (gains) losses on cash flow hedges	$ 10	$ 4
Reclassification adjustment for net realized (gains) losses on cash flow hedges			$ 6