Condensed Consolidating Supplemental Guarantor Information - Statements of Operations and Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Total revenue	$ 1,536	$ 1,517
Selling, general and administrative expenses	252	245
Research and development expenses	59	66
Total operating expenses	1,436	1,408
Income from operations	100	109
Interest expense	(45)	(41)
Other expense, net	(8)	(5)
Income from continuing operations before income taxes	47	63
Income tax expense (benefit)	9	7
Income (loss) from continuing operations before earnings in subsidiaries	38	56
Equity in earnings of consolidated subsidiaries	0	0
Income from continuing operations	38	56
Income (loss) from discontinued operations, net of tax	0	(35)
Net income	38	21
Net income attributable to noncontrolling interests	1	1
Net income attributable to NCR	37	20
Total comprehensive income (loss)	54	36
Less comprehensive income (loss) attributable to noncontrolling interests	1	1
Comprehensive income attributable to NCR	53	35
Product
Total revenue	539	526
Cost of revenue	453	420
Services
Total revenue	997	991
Cost of revenue	672	677
Eliminations
Total revenue	(46)	(38)
Selling, general and administrative expenses	0	0
Research and development expenses	0	0
Total operating expenses	(46)	(38)
Income from operations	0	0
Interest expense	3	1
Other expense, net	(3)	(1)
Income from continuing operations before income taxes	0	0
Income tax expense (benefit)	0	0
Income (loss) from continuing operations before earnings in subsidiaries	0	0
Equity in earnings of consolidated subsidiaries	(212)	(135)
Income from continuing operations	(212)	(135)
Income (loss) from discontinued operations, net of tax	0	0
Net income	(212)	(135)
Net income attributable to noncontrolling interests	0	0
Net income attributable to NCR	(212)	(135)
Total comprehensive income (loss)	(243)	(149)
Less comprehensive income (loss) attributable to noncontrolling interests	0	0
Comprehensive income attributable to NCR	(243)	(149)
Eliminations | Product
Total revenue	(46)	(38)
Cost of revenue	(46)	(38)
Eliminations | Services
Total revenue	0	0
Cost of revenue	0	0
Parent Issuer
Total revenue	789	794
Selling, general and administrative expenses	139	164
Research and development expenses	33	46
Total operating expenses	777	781
Income from operations	12	13
Interest expense	(43)	(39)
Other expense, net	(13)	(3)
Income from continuing operations before income taxes	(44)	(29)
Income tax expense (benefit)	38	(8)
Income (loss) from continuing operations before earnings in subsidiaries	(82)	(21)
Equity in earnings of consolidated subsidiaries	119	76
Income from continuing operations	37	55
Income (loss) from discontinued operations, net of tax	0	(35)
Net income	37	20
Net income attributable to noncontrolling interests	0	0
Net income attributable to NCR	37	20
Total comprehensive income (loss)	53	35
Less comprehensive income (loss) attributable to noncontrolling interests	0	0
Comprehensive income attributable to NCR	53	35
Parent Issuer | Product
Total revenue	272	277
Cost of revenue	244	229
Parent Issuer | Services
Total revenue	517	517
Cost of revenue	361	342
Guarantor Subsidiary
Total revenue	11	13
Selling, general and administrative expenses	1	1
Research and development expenses	0	0
Total operating expenses	6	8
Income from operations	5	5
Interest expense	0	0
Other expense, net	2	1
Income from continuing operations before income taxes	7	6
Income tax expense (benefit)	(1)	2
Income (loss) from continuing operations before earnings in subsidiaries	8	4
Equity in earnings of consolidated subsidiaries	93	59
Income from continuing operations	101	63
Income (loss) from discontinued operations, net of tax	0	0
Net income	101	63
Net income attributable to noncontrolling interests	0	0
Net income attributable to NCR	101	63
Total comprehensive income (loss)	117	62
Less comprehensive income (loss) attributable to noncontrolling interests	0	0
Comprehensive income attributable to NCR	117	62
Guarantor Subsidiary | Product
Total revenue	3	5
Cost of revenue	2	4
Guarantor Subsidiary | Services
Total revenue	8	8
Cost of revenue	3	3
Non-Guarantor Subsidiaries
Total revenue	782	748
Selling, general and administrative expenses	112	80
Research and development expenses	26	20
Total operating expenses	699	657
Income from operations	83	91
Interest expense	(5)	(3)
Other expense, net	6	(2)
Income from continuing operations before income taxes	84	86
Income tax expense (benefit)	(28)	13
Income (loss) from continuing operations before earnings in subsidiaries	112	73
Equity in earnings of consolidated subsidiaries	0	0
Income from continuing operations	112	73
Income (loss) from discontinued operations, net of tax	0	0
Net income	112	73
Net income attributable to noncontrolling interests	1	1
Net income attributable to NCR	111	72
Total comprehensive income (loss)	127	88
Less comprehensive income (loss) attributable to noncontrolling interests	1	1
Comprehensive income attributable to NCR	126	87
Non-Guarantor Subsidiaries | Product
Total revenue	310	282
Cost of revenue	253	225
Non-Guarantor Subsidiaries | Services
Total revenue	472	466
Cost of revenue	$ 308	$ 332