Restructuring Plan Restructuring and Related Costs (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring and other asset-related charges	$ 9	$ 33
Payments for Restructuring		7
Restructuring Reserve, Period Increase (Decrease)		9
inventory related charges [Member] \| Cost of Services [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other asset-related charges	7	24
Other exit costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other asset-related charges	2	4
Other exit costs [Member] \| Selling, General and Administrative Expenses [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other asset-related charges	2	3
Other exit costs [Member] \| Cost of Products [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other asset-related charges	0	1
Severance charge under ASC 420 [Member] \| Severance and other employee related charges [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other asset-related charges	2
Payments for Restructuring	2	3
Discrete charge under ASC 712 [Member] \| Severance and other employee related charges [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other asset-related charges	(2)
Payments for Restructuring	$ 0	$ 0

Restructuring and other asset-related charges (benefit)

No definition available.

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Namespace Prefix:	ncr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 17
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3367-108585

+ Details

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Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of increase (decrease) in the accrual for restructuring costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

+ Details

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- Details

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- Details

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