Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Product revenue	$ 2,711	$ 2,892	$ 2,912
Service revenue	3,662	3,699	3,211
Total revenue	6,373	6,591	6,123
Cost of products	2,072	2,153	2,152
Cost of services	2,832	2,706	2,231
Selling, general and administrative expenses	1,042	1,012	871
Research and development expenses	230	263	203
Restructuring-related charges	62	104	0
Total operating expenses	6,238	6,238	5,457
Income from operations	135	353	666
Interest expense	(173)	(181)	(103)
Other (expense), net	(57)	(35)	(9)
(Loss) income from continuing operations before income taxes	(95)	137	554
Income tax expense (benefit)	55	(48)	98
(Loss) income from continuing operations	(150)	185	456
Loss (income) from discontinued operations	24	(10)	9
Net (loss) income	(174)	195	447
Net income attributable to noncontrolling interests	4	4	4
Net (loss) income attributable to NCR	(178)	191	443
Amounts attributable to NCR common stockholders:
(Loss) income from continuing operations	(154)	181	452
Dividends on convertible preferred stock	(4)	0	0
income (loss) from continuing operations attributable to common stockholders	(158)	181	452
Loss (income) from discontinued operations	(24)	10	(9)
Net (loss) income attributable to NCR common stockholders	$ (182)	$ 191	$ 443
(Loss) income per share attributable to NCR common stockholders:
Basic (in dollars per share)	$ (0.94)	$ 1.08	$ 2.73
Diluted (in dollars per share)	(0.94)	1.06	2.67
Net (loss) income per common share
Basic (in dollars per share)	(1.09)	1.14	2.68
Total diluted earnings (loss) per share	$ (1.09)	$ 1.12	$ 2.62
Weighted average common shares outstanding
Basic (in shares)	167.6	167.9	165.4
Diluted (in shares)	167.6	171.2	169.3