Description of Business and Significant Accounting Policies Description of Business and Significant Accounting Policies - Earnings Per Share (Basic) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share [Abstract]
Income (loss) from continuing operations	$ 68	$ 107	$ 76	$ 32	$ 44	$ 102	$ (344)	$ 40	$ 283	$ (154)	$ 181
Preferred Stock Dividends, Income Statement Impact									49	4	0
Preferred Stock Dividends Income Statement Impact Included in Diluted Earnings Per Share From Continuing Operations									0
Income (loss) from continuing operations attributable to common stockholders									234	(158)	181
Income (loss) from discontinued operations, net of tax	$ (11)	$ (2)	$ 0	$ 0	$ (20)	$ (4)	$ 0	$ 0	(13)	(24)	10
Net income (loss) attributable to NCR common stockholders									$ 221	$ (182)	$ 191
Basic (in shares)									125.6	167.6	167.9
Basic (in dollars per share)	$ 0.45	$ 0.76	$ 0.51	$ 0.16	$ 0.27	$ 0.60	$ (2.03)	$ 0.24	$ 1.86	$ (0.94)	$ 1.08
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic Share									(0.10)	(0.15)	0.06
Basic (in dollars per share)	$ 0.36	$ 0.74	$ 0.51	$ 0.16	$ 0.15	$ 0.58	$ (2.03)	$ 0.24	$ 1.76	$ (1.09)	$ 1.14