Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 1,747	$ 1,739
Accumulated Amortization	(369)	(175)
Net Carrying Value	1,378	1,564
Rider and Merchant relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	1,051	1,007
Accumulated Amortization	(172)	(81)
Net Carrying Value	$ 879	$ 926
Weighted Average Remaining Useful Life - Years	4 years	8 years
Developed technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 492	$ 529
Accumulated Amortization	(158)	(69)
Net Carrying Value	$ 334	$ 460
Weighted Average Remaining Useful Life - Years	2 years	2 years
Trade names and trademarks
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 184	$ 183
Accumulated Amortization	(30)	(16)
Net Carrying Value	$ 154	$ 167
Weighted Average Remaining Useful Life - Years	6 years	7 years
Patents
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 15	$ 15
Accumulated Amortization	(6)	(6)
Net Carrying Value	$ 9	$ 9
Weighted Average Remaining Useful Life - Years	7 years	8 years
Other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 5	$ 5
Accumulated Amortization	(3)	(3)
Net Carrying Value	$ 2	$ 2
Weighted Average Remaining Useful Life - Years	0 years	0 years

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 50
-Paragraph 2
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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 926
-SubTopic 20
-Section 50
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Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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