Condensed Consolidated Statements of Operations (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Income Statement [Abstract]
Product revenue	$ 701	$ 712	$ 2,111	$ 1,988
Service revenue	807	723	2,342	2,100
Total revenue	1,508	1,435	4,453	4,088
Cost of products	524	534	1,577	1,511
Cost of services	569	519	1,666	1,506
Selling, general and administrative expenses	217	206	678	592
Research and development expenses	53	47	163	142
Total operating expenses	1,363	1,306	4,084	3,751
Income from operations	145	129	369	337
Interest expense	(23)	(7)	(70)	(24)
Other (expense), net	(3)	0	(4)	(7)
Income from continuing operations before income taxes	119	122	295	306
Income tax expense	19	33	44	68
Income from continuing operations	100	89	251	238
(Loss) income from discontinued operations, net of tax	0	(1)	(1)	3
Net income (loss)	100	88	250	241
Net income attributable to noncontrolling interests	2	1	5	2
Net income (loss) attributable to NCR	98	87	245	239
Amounts attributable to NCR common stockholders:
Income from continuing operations	98	88	246	236
(Loss) income from discontinued operations, net of tax	0	(1)	(1)	3
Net income (loss)	$ 98	$ 87	$ 245	$ 239
Income per share attributable to NCR common stockholders:
Basic (in dollars per share)	$ 0.59	$ 0.55	$ 1.49	$ 1.49
Diluted (in dollars per share)	$ 0.58	$ 0.53	$ 1.46	$ 1.44
Net income per common share
Basic (in dollars per share)	$ 0.59	$ 0.55	$ 1.48	$ 1.50
Diluted (in dollars per share)	$ 0.58	$ 0.53	$ 1.45	$ 1.46
Weighted average common shares outstanding
Basic (in shares)	166.2	159.6	165.1	158.9
Diluted (in shares)	170.0	164.8	168.8	164.0