Goodwill (Details) - USD ($) $ in Millions		1 Months Ended	12 Months Ended
Dec. 04, 2019	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Line Items]
Goodwill, beginning balance			$ 5,702	$ 5,590
Acquisitions and valuation adjustments			30,482	247
Dispositions			(2)	(131)
Goodwill reclassified to assets held for sale			(220)
Foreign currency translation			76	(4)
Goodwill, ending balance		$ 36,038	36,038	5,702
First Data
Goodwill [Line Items]
Goodwill, beginning balance			0	0
Acquisitions and valuation adjustments			30,507	0
Dispositions			0	0
Goodwill reclassified to assets held for sale			0
Foreign currency translation			74	0
Goodwill, ending balance		30,581	30,581	0
Payments
Goodwill [Line Items]
Goodwill, beginning balance			3,996	3,757
Acquisitions and valuation adjustments			(27)	240
Dispositions			0	0
Goodwill reclassified to assets held for sale			(220)
Foreign currency translation			0	(1)
Goodwill, ending balance		3,749	3,749	3,996
Financial
Goodwill [Line Items]
Goodwill, beginning balance			1,706	1,833
Acquisitions and valuation adjustments			2	7
Dispositions			(2)	(131)
Goodwill reclassified to assets held for sale			0
Foreign currency translation			2	(3)
Goodwill, ending balance		$ 1,708	$ 1,708	$ 1,706
Investment Services Business \| Payments
Goodwill [Line Items]
Controlling interest sold (as a percent)	60.00%	60.00%

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