Revenue Recognition - Disaggregation of Revenue (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Capitalized Contract Cost, Impairment Loss	$ 0	$ 0
Revenue from contract with customer	1,412,000,000	4,272,000,000
Digital Money Movement
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	363,000,000	1,071,000,000
Card and Related Services
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	401,000,000	1,215,000,000
Other
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	80,000,000	237,000,000
Total Payments
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	844,000,000	2,523,000,000
Account and Item Processing
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	516,000,000	1,552,000,000
Lending Solutions
Disaggregation of Revenue [Line Items]
Revenue from contract with customer		56,000,000
Other
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	58,000,000	172,000,000
Total Financial
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	574,000,000	1,780,000,000
Payments
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	844,000,000	2,523,000,000
Payments \| Digital Money Movement
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	363,000,000	1,071,000,000
Payments \| Card and Related Services
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	401,000,000	1,215,000,000
Payments \| Other
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	80,000,000	237,000,000
Payments \| Total Payments
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	844,000,000	2,523,000,000
Payments \| Account and Item Processing
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0
Payments \| Lending Solutions
Disaggregation of Revenue [Line Items]
Revenue from contract with customer		0
Payments \| Other
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0
Payments \| Total Financial
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0
Financial
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	574,000,000	1,780,000,000
Financial \| Digital Money Movement
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0
Financial \| Card and Related Services
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0
Financial \| Other
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0
Financial \| Total Payments
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0
Financial \| Account and Item Processing
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	516,000,000	1,552,000,000
Financial \| Lending Solutions
Disaggregation of Revenue [Line Items]
Revenue from contract with customer		56,000,000
Financial \| Other
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	58,000,000	172,000,000
Financial \| Total Financial
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	574,000,000	1,780,000,000
Corporate and Other
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	(6,000,000)	(31,000,000)
Corporate and Other \| Digital Money Movement
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0
Corporate and Other \| Card and Related Services
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0
Corporate and Other \| Other
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0
Corporate and Other \| Total Payments
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0
Corporate and Other \| Account and Item Processing
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0
Corporate and Other \| Lending Solutions
Disaggregation of Revenue [Line Items]
Revenue from contract with customer		0
Corporate and Other \| Other
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0
Corporate and Other \| Total Financial
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0
Corporate and Other \| Payments
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0
Corporate and Other \| Financial
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	$ 0	$ 0
Geographic Concentration Risk \| Sales Revenue, Net \| Foreign Tax Authority
Disaggregation of Revenue [Line Items]
Percentage of concentration risk		5.00%

Amount of impairment loss for asset recognized from cost incurred to obtain or fulfill contract with customer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-Section 32
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-URI http://asc.fasb.org/extlink&oid=82859839&loc=SL82860478-203043

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