Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 89	$ 86	$ 215	$ (39)
Currency translation adjustments
Currency translation gains (losses)	(22)	(13)	(11)	(43)
Derivatives
Unrealized gains on derivatives	4	1	5	5
Gains on derivatives recognized during the period	(2)	(2)	(5)	(2)
Less income tax provision	(1)	(1)	0	(1)
Employee benefit plans
Amortization of prior service benefit	(1)	(2)	(5)	(7)
Amortization of actuarial (losses) gains	0	0	(1)	1
Less income tax benefit	1	0	1	1
Other comprehensive income (loss)	(21)	(17)	(16)	(46)
Total comprehensive income (loss)	68	69	199	(85)
Less comprehensive income attributable to noncontrolling interests:
Net income (loss)	(1)	2	0	2
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Noncontrolling Interest	(1)	1	(1)	(2)
Amounts attributable to noncontrolling interests	(2)	3	(1)	0
Comprehensive income (loss) attributable to NCR	$ 70	$ 66	$ 200	$ (85)