Condensed Consolidating Supplemental Guarantor Information - Balance Sheet (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Current assets
Cash and cash equivalents	$ 335	$ 464	$ 343
Accounts receivable, net	1,430	1,356
Inventories	868	806
Due from affiliates	0	0
Other current assets	402	397
Total current assets	3,035	3,023
Property, plant and equipment, net	372	359
Goodwill	2,707	2,692
Intangibles, net	553	595
Operating lease assets	414	0
Prepaid pension cost	151	140
Deferred income taxes	468	448
Investments in subsidiaries	0	0
Due from affilates	0	0
Other assets	522	504
Total assets	8,222	7,761
Current liabilities
Short-term borrowings	198	185
Accounts payable	769	897
Payroll and benefits liabilities	235	238
Contract liabilities	546	461
Due to affiliates	0	0
Other current liabilities	555	501
Total current liabilities	2,303	2,282
Long-term debt	2,918	2,980
Pension and indemnity plan liabilities	767	759
Postretirement and postemployment benefits liabilities	120	118
Income tax accruals	94	91
Due to affiliates	0	0
Operating lease liabilities	389	0
Other liabilities	186	259
Total liabilities	6,777	6,489
Redeemable noncontrolling interest	14	14
Series A convertible preferred stock	884	859
Stockholders’ equity
Total NCR stockholders’ equity	542	395
Noncontrolling interests in subsidiaries	5	4
Total stockholders’ equity	547	399
Total liabilities and stockholders’ equity	8,222	7,761
Eliminations
Current assets
Cash and cash equivalents	0	0	0
Accounts receivable, net	0	0
Inventories	0	0
Due from affiliates	(3,315)	(3,257)
Other current assets	0	(42)
Total current assets	(3,315)	(3,299)
Property, plant and equipment, net	0	0
Goodwill	0	0
Intangibles, net	0	0
Operating lease assets	0
Prepaid pension cost	0	0
Deferred income taxes	0	(18)
Investments in subsidiaries	(6,527)	(6,098)
Due from affilates	(17)	(52)
Other assets	0	0
Total assets	(9,859)	(9,467)
Current liabilities
Short-term borrowings	0	0
Accounts payable	0	0
Payroll and benefits liabilities	0	0
Contract liabilities	0	0
Due to affiliates	(3,315)	(3,257)
Other current liabilities	0	(42)
Total current liabilities	(3,315)	(3,299)
Long-term debt	0	0
Pension and indemnity plan liabilities	0	0
Postretirement and postemployment benefits liabilities	0	0
Income tax accruals	0	0
Due to affiliates	(17)	(52)
Operating lease liabilities	0
Other liabilities	0	(18)
Total liabilities	(3,332)	(3,369)
Redeemable noncontrolling interest	0	0
Series A convertible preferred stock	0	0
Stockholders’ equity
Total NCR stockholders’ equity	(6,527)	(6,098)
Noncontrolling interests in subsidiaries	0	0
Total stockholders’ equity	(6,527)	(6,098)
Total liabilities and stockholders’ equity	(9,859)	(9,467)
Parent Issuer
Current assets
Cash and cash equivalents	18	6	11
Accounts receivable, net	57	37
Inventories	309	288
Due from affiliates	830	708
Other current assets	143	137
Total current assets	1,357	1,176
Property, plant and equipment, net	260	245
Goodwill	2,199	2,168
Intangibles, net	498	536
Operating lease assets	270
Prepaid pension cost	0	0
Deferred income taxes	315	317
Investments in subsidiaries	3,477	3,244
Due from affilates	16	16
Other assets	465	453
Total assets	8,857	8,155
Current liabilities
Short-term borrowings	94	85
Accounts payable	365	397
Payroll and benefits liabilities	125	141
Contract liabilities	294	221
Due to affiliates	2,478	2,177
Other current liabilities	208	201
Total current liabilities	3,564	3,222
Long-term debt	2,915	2,978
Pension and indemnity plan liabilities	514	502
Postretirement and postemployment benefits liabilities	17	18
Income tax accruals	25	19
Due to affiliates	0	0
Operating lease liabilities	297
Other liabilities	99	162
Total liabilities	7,431	6,901
Redeemable noncontrolling interest	0	0
Series A convertible preferred stock	884	859
Stockholders’ equity
Total NCR stockholders’ equity	542	395
Noncontrolling interests in subsidiaries	0	0
Total stockholders’ equity	542	395
Total liabilities and stockholders’ equity	8,857	8,155
Guarantor Subsidiary
Current assets
Cash and cash equivalents	2	8	6
Accounts receivable, net	1	10
Inventories	1	4
Due from affiliates	2,081	2,092
Other current assets	2	47
Total current assets	2,087	2,161
Property, plant and equipment, net	0	1
Goodwill	0	0
Intangibles, net	0	0
Operating lease assets	0
Prepaid pension cost	0	0
Deferred income taxes	3	0
Investments in subsidiaries	3,050	2,854
Due from affilates	1	1
Other assets	1	4
Total assets	5,142	5,021
Current liabilities
Short-term borrowings	0	0
Accounts payable	0	2
Payroll and benefits liabilities	0	0
Contract liabilities	1	5
Due to affiliates	109	143
Other current liabilities	1	6
Total current liabilities	111	156
Long-term debt	0	0
Pension and indemnity plan liabilities	0	0
Postretirement and postemployment benefits liabilities	4	3
Income tax accruals	0	5
Due to affiliates	0	36
Operating lease liabilities	0
Other liabilities	0	24
Total liabilities	115	224
Redeemable noncontrolling interest	0	0
Series A convertible preferred stock	0	0
Stockholders’ equity
Total NCR stockholders’ equity	5,027	4,797
Noncontrolling interests in subsidiaries	0	0
Total stockholders’ equity	5,027	4,797
Total liabilities and stockholders’ equity	5,142	5,021
Non-Guarantor Subsidiaries
Current assets
Cash and cash equivalents	315	450	$ 326
Accounts receivable, net	1,372	1,309
Inventories	558	514
Due from affiliates	404	457
Other current assets	257	255
Total current assets	2,906	2,985
Property, plant and equipment, net	112	113
Goodwill	508	524
Intangibles, net	55	59
Operating lease assets	144
Prepaid pension cost	151	140
Deferred income taxes	150	149
Investments in subsidiaries	0	0
Due from affilates	0	35
Other assets	56	47
Total assets	4,082	4,052
Current liabilities
Short-term borrowings	104	100
Accounts payable	404	498
Payroll and benefits liabilities	110	97
Contract liabilities	251	235
Due to affiliates	728	937
Other current liabilities	346	336
Total current liabilities	1,943	2,203
Long-term debt	3	2
Pension and indemnity plan liabilities	253	257
Postretirement and postemployment benefits liabilities	99	97
Income tax accruals	69	67
Due to affiliates	17	16
Operating lease liabilities	92
Other liabilities	87	91
Total liabilities	2,563	2,733
Redeemable noncontrolling interest	14	14
Series A convertible preferred stock	0	0
Stockholders’ equity
Total NCR stockholders’ equity	1,500	1,301
Noncontrolling interests in subsidiaries	5	4
Total stockholders’ equity	1,505	1,305
Total liabilities and stockholders’ equity	$ 4,082	$ 4,052