Segment Information and Concentrations - Revenue and Operating Income By Segments (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) segment	Jun. 30, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments \| segment			3
Revenues	$ 1,537	$ 1,593	$ 3,054	$ 3,071
Asset Impairment Charges	183	0	183	0
(Loss) income from operations	(106)	175	3	290
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	1,537	1,593	3,054	3,071
Operating income by segment	165	212	313	370
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Transformation and restructuring costs	66	8	82	21
Asset Impairment Charges	183	0	183	0
Acquisition-related amortization of intangible assets	21	28	44	57
Acquisition-related costs	1	1	1	2
Other adjustments	271	37	310	80
ATM [Domain] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	180	227	375	436
SCO [Domain] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	99	96	176	197
POS [Domain] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	178	213	362	367
IPS [Domain] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	0	5	0	10
Software license [Domain] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	68	77	138	162
Software Maintenance [Domain] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	93	91	184	183
Cloud [Domain] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	155	145	310	287
Professional Services [Domain] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	154	151	298	284
Software \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	470	464	930	916
Operating income by segment	115	127	224	251
Services \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	610	588	1,211	1,145
Operating income by segment	77	74	139	118
Hardware \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	457	541	913	1,010
Operating income by segment	$ (27)	$ 11	$ (50)	$ 1

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Acquisition Related Costs Included In Other Adjustments

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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