Consolidated Statements of Operations (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Product revenue									$ 2,912	$ 2,854	$ 2,592
Service revenue									3,211	2,876	2,699
Total revenue	1,670	1,508	1,535	1,410	1,642	1,435	1,409	1,244	6,123	5,730	5,291
Cost of products									2,152	2,144	2,022
Cost of services									2,231	1,941	2,318
Selling, general and administrative expenses									871	742	890
Research and development expenses									203	155	209
Total operating expenses									5,457	4,982	5,439
Income (loss) from operations	297	145	139	85	411	129	130	78	666	748	(148)
Interest expense									(103)	(42)	(13)
Other (expense) income, net									(9)	(8)	(3)
Income (loss) from continuing operations before income taxes									554	698	(164)
Income tax expense (benefit)									98	223	(66)
Income (loss) from continuing operations									456	475	(98)
(Loss) income from discontinued operations, net of tax									(9)	6	(93)
Net income (loss)									447	481	(191)
Net income (loss) attributable to noncontrolling interests									4	0	(1)
Net income (loss) attributable to NCR	198	98	86	61	242	87	102	50	443	481	(190)
Amounts attributable to NCR common stockholders:
Income (loss) from continuing operations	206	98	86	62	239	88	89	59	452	475	(97)
Income (loss) from discontinued operations, net of tax	(8)	0	0	(1)	3	(1)	13	(9)	(9)	6	(93)
Net income (loss) attributable to NCR common stockholders									$ 443	$ 481	$ (190)
Net income per common share from continuing operations
Basic (in dollars per share)	$ 1.24	$ 0.59	$ 0.52	$ 0.38	$ 1.49	$ 0.55	$ 0.56	$ 0.37	$ 2.73	$ 2.98	$ (0.61)
Diluted (in dollars per share)	$ 1.21	$ 0.58	$ 0.51	$ 0.37	$ 1.45	$ 0.53	$ 0.54	$ 0.36	$ 2.67	$ 2.90	$ (0.61)
Net income (loss) per common share
Basic (in dollars per share)	$ 1.19	$ 0.59	$ 0.52	$ 0.37	$ 1.51	$ 0.55	$ 0.64	$ 0.32	$ 2.68	$ 3.02	$ (1.20)
Diluted (in dollars per share)	$ 1.16	$ 0.58	$ 0.51	$ 0.36	$ 1.47	$ 0.53	$ 0.62	$ 0.31	$ 2.62	$ 2.94	$ (1.20)
Weighted average common shares outstanding
Basic (in shares)											161.0
Diluted (in shares)									169.3	163.8	158.0