Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Net income (loss)	$ 235	$ 274	$ (174)
Currency translation adjustments
Currency translation adjustments	39	(57)	(50)
Derivatives
Unrealized gain (loss) on derivatives	(16)	19	10
Gains on derivatives arising during the period	(1)	(1)	(7)
Less income tax benefit (expense)	3	(4)	(1)
Employee benefit plans
New prior service benefit (cost)	0	0	9
Amortization of prior service cost	(11)	(19)	(21)
Net (loss) gain arising during the period	(13)	(1)	43
Amortization of actuarial (loss) gain	(2)	(2)	2
Less income tax benefit (expense)	5	5	(2)
Other comprehensive income (loss)	4	(60)	(17)
Total comprehensive income (loss)	239	214	(191)
Less comprehensive income attributable to noncontrolling interests:
Net income	3	4	4
Currency translation adjustments	(2)	(5)	(3)
Amounts attributable to noncontrolling interests	1	(1)	1
Comprehensive income (loss) attributable to NCR common stockholders	$ 238	$ 215	$ (192)