Segment Information - Revenue and Operating Income By Segments (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019		Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Total revenue									$ 6,915		$ 6,405	$ 6,516
Income from operations	$ 182	$ 172	$ 157	$ 100	$ 63	$ 125	$ (106)	$ 109	611		191	691
Asset Impairment Charges									0		227	0
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenue									6,915		6,405	6,516
Operating income by segment									758		688	840
Operating Segments [Member] | Banking Segment [Member]
Segment Reporting Information [Line Items]
Total revenue									3,512		3,183	3,175
Operating income by segment									514		412	421
Operating Segments [Member] | Retail Segment [Member]
Segment Reporting Information [Line Items]
Total revenue									2,217		2,097	2,169
Operating income by segment									144		142	231
Operating Segments [Member] | Hospitality
Segment Reporting Information [Line Items]
Total revenue									843		817	878
Operating income by segment									56		85	140
Operating Segments [Member] | Other Segments [Member]
Segment Reporting Information [Line Items]
Total revenue									343		308	294
Operating income by segment									44		49	48
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Other adjustments									147	[1]	497	149
Restructuring and other asset-related charges									58		223	29
Acquisition Related Amortization Costs Included in Other Adjustments									86		85	115
Acquisiton Related Costs Included In Other Adjustments									3		6	5
Asset Impairment Charges									$ 0		$ 183	$ 0

[1]
⁽¹⁾ The following table presents the other adjustments for NCR fo