Accumulated Other Comprehensive Income (Loss) (AOCI) Reclassifications (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative expenses	$ (1,051)	$ (1,005)	$ (923)
Research and development expenses	(259)	(252)	(241)
Interest expense	(197)	(168)	(163)
Income (loss) from continuing operations	614	(34)	240
Income tax expense (benefit)	(273)	73	242
Net income (loss) attributable to NCR common stockholders	454	(137)	123
Reclassification out of Accumulated Other Comprehensive Income
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative expenses	(4)	3	(4)
Research and development expenses	0	1	(2)
Income (loss) from continuing operations	(17)	(16)	(14)
Income tax expense (benefit)	5	2	5
Net income (loss) attributable to NCR common stockholders	(12)	(14)	(9)
Reclassification out of Accumulated Other Comprehensive Income | Actuarial losses recognized
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative expenses	(1)	0	0
Research and development expenses	0	0	(1)
Income (loss) from continuing operations	(3)	0	(2)
Reclassification out of Accumulated Other Comprehensive Income | Amortization of prior service benefit
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative expenses	(3)	(3)	(4)
Research and development expenses	0	1	(1)
Income (loss) from continuing operations	(6)	(9)	(11)
Reclassification out of Accumulated Other Comprehensive Income | Effective Cash Flow Hedges
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative expenses	0	0	0
Research and development expenses	0	0	0
Income (loss) from continuing operations	(8)	(7)	(1)
Product [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Cost of products	2,146	1,988	2,021
Product [Member] | Reclassification out of Accumulated Other Comprehensive Income
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Cost of products	(8)	7	1
Product [Member] | Reclassification out of Accumulated Other Comprehensive Income | Actuarial losses recognized
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Cost of products	0	0	0
Product [Member] | Reclassification out of Accumulated Other Comprehensive Income | Amortization of prior service benefit
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Cost of products	0	0	0
Product [Member] | Reclassification out of Accumulated Other Comprehensive Income | Effective Cash Flow Hedges
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Cost of products	(8)	(7)	1
Service [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Cost of products	2,848	2,742	2,640
Service [Member] | Reclassification out of Accumulated Other Comprehensive Income
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Cost of products	5	5	7
Service [Member] | Reclassification out of Accumulated Other Comprehensive Income | Actuarial losses recognized
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Cost of products	2	0	1
Service [Member] | Reclassification out of Accumulated Other Comprehensive Income | Amortization of prior service benefit
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Cost of products	3	(5)	6
Service [Member] | Reclassification out of Accumulated Other Comprehensive Income | Effective Cash Flow Hedges
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Cost of products	$ 0	$ 0	$ 0