Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Net income	$ 752	$ 576
Other comprehensive (loss) income:
Fair market value adjustment on derivatives	1	5
Tax impacts of derivatives	(1)	(3)
Unrealized (loss) gain on defined benefit pension plans	(84)	3
Tax impacts of defined benefit pension plans	21	(1)
Foreign currency translation	(133)	115
Tax impacts of foreign currency translation	(31)	22
Total other comprehensive (loss) income	(224)	147
Comprehensive income	528	723
Less: net income attributable to noncontrolling interests and redeemable noncontrolling interest	17	13
Less: other comprehensive (loss) income attributable to noncontrolling interests	(13)	12
Comprehensive income attributable to Fiserv, Inc.	524	698
Foreign currency forward exchange contracts
Other comprehensive (loss) income:
Reclassification adjustment for net realized (gains) losses on cash flow hedges	(1)	1
Treasury Lock
Other comprehensive (loss) income:
Reclassification adjustment for net realized (gains) losses on cash flow hedges	$ 4	$ 5