Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 119	$ 107	$ 278	$ 213
Currency translation adjustments
Currency translation gains (losses)	6	3	35	(23)
Derivatives
Unrealized (losses) gains on derivatives	(5)	4	(15)	4
(Gains) losses on derivatives recognized during the period	1	0	(2)	2
Less income tax benefit (expense)	0	(1)	3	(1)
Employee benefit plans
Amortization of prior service benefit	(1)	(4)	(6)	(14)
Amortization of actuarial benefit	(1)	0	(2)	(1)
Less income tax benefit	0	1	2	4
Other comprehensive (loss) income	0	3	15	(29)
Total comprehensive income	119	110	293	184
Less comprehensive income attributable to noncontrolling interests:
Net income (loss)	1	2	1	0
Currency translation losses	(2)	(1)	(2)	(7)
Amounts attributable to noncontrolling interests	(1)	1	(1)	(7)
Comprehensive income attributable to NCR	$ 120	$ 109	$ 294	$ 191