Income Taxes - Unrecognized Tax Benefit (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Gross unrecognized tax benefits - January 1	$ 209	$ 248	$ 277
Increases related to tax positions from prior years	3	17	34
Decreases related to tax positions from prior years	(34)	(37)	(50)
Increases related to tax provisions taken during the current year	23	35	43
Settlements with tax authorities	(6)	(33)	(14)
Lapses of statutes of limitation	(12)	(21)	(42)
Total Gross unrecognized tax benefits - December 31	183	209	248
Total amount of gross unrecognized tax benefits that would affect NCR's effective tax rate if realized	94
Recognized interest and penalties expense (benefit) associated with uncertain tax positions	0	4	$ (1)
Interest and penalties accrued associated with uncertain tax positions	41	$ 46
Undistributed earnings of foreign subsidiaries	2,300
Minimum [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Significant change in unrecognized tax benefits is reasonably possible, estimated range of change, upper bound	35
Maximum [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Significant change in unrecognized tax benefits is reasonably possible, estimated range of change, upper bound	$ 40