Debt Obligations - Senior Unsecured Notes (Details) - USD ($) $ in Millions			9 Months Ended
	Aug. 20, 2020	Apr. 13, 2020	Sep. 30, 2020	Dec. 31, 2019	Aug. 21, 2019	Dec. 19, 2013	Sep. 17, 2012
Debt Instrument [Line Items]
Deferred Financing Fees Written Off			$ 5
Debt Premium Cost Incurred			$ 15
5.00% Senior Notes due 2022
Debt Instrument [Line Items]
Long-term Debt							$ 600
Debt stated interest rate			500.00%	500.00%
Debt Instrument, Redemption Price, Percentage			100.00%
6.375% Senior Notes due 2023
Debt Instrument [Line Items]
Long-term Debt						$ 700
Debt stated interest rate			6.375%	6.375%
Debt Instrument, Redemption Price, Percentage			102.125%
5.750% Senior Notes due 2027 [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 500
Debt stated interest rate			5.75%	5.75%	5.75%
Debt percentage of principle amount notes were sold at					100.00%
6.125% Senior Notes due 2029 [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 500
Debt stated interest rate			6.125%	6.125%	6.125%
8.125% Notes Due 2025 [Member]
Debt Instrument [Line Items]
Long-term Debt			$ 400
Debt stated interest rate			8.125%
Debt Instrument Redemption Price As Percentage of Principle Amount		100.00%
Debt percentage of principle amount notes were sold at		100.00%
5.000% Senior Notes due 2028
Debt Instrument [Line Items]
Debt stated interest rate			5.00%
Debt percentage of principle amount notes were sold at	100.00%
Aggregate principle amount of Notes required to remain outstanding	0.55
Date of equity offering offering when paying unsecured debt	180 days
5.250% Senior Notes due 2030
Debt Instrument [Line Items]
Debt stated interest rate			5.25%	5.25%
Debt percentage of principle amount notes were sold at	100.00%
Aggregate principle amount of Notes required to remain outstanding	0.55
Date of equity offering offering when paying unsecured debt	180 days
From time to time, prior to October 1, 2023 [Member] | 5.000% Senior Notes due 2028
Debt Instrument [Line Items]
Debt Instrument Redemption Price As Percentage of Principle Amount	40.00%
Debt Instrument, Redemption Price, Percentage	105.00%
From time to time, prior to October 1, 2023 [Member] | 5.250% Senior Notes due 2030
Debt Instrument [Line Items]
Debt Instrument Redemption Price As Percentage of Principle Amount	40.00%
Debt Instrument, Redemption Price, Percentage	105.25%
Prior to October 1, 2023 [Member] | 5.000% Senior Notes due 2028
Debt Instrument [Line Items]
Debt Instrument Redemption Price As Percentage of Principle Amount	100.00%
Prior to October 1, 2025 [Member] | 5.250% Senior Notes due 2030
Debt Instrument [Line Items]
Debt Instrument Redemption Price As Percentage of Principle Amount	100.00%
Twelve month period commencing on October 1, 2023 [Member] | 5.000% Senior Notes due 2028
Debt Instrument [Line Items]
Debt Instrument Redemption Price As Percentage of Principle Amount	102.50%
Twelve Month Period Commencing October 1, 2024 [Member] | 5.000% Senior Notes due 2028
Debt Instrument [Line Items]
Debt Instrument Redemption Price As Percentage of Principle Amount	101.25%
Twelve month period commencing on October 1, 2025 [Member] | 5.000% Senior Notes due 2028
Debt Instrument [Line Items]
Debt Instrument Redemption Price As Percentage of Principle Amount	100.00%
Twelve month period commencing on October 1, 2025 [Member] | 5.250% Senior Notes due 2030
Debt Instrument [Line Items]
Debt Instrument Redemption Price As Percentage of Principle Amount	102.625%
Twelve Month Period Commencing October 1, 2026 [Member] | 5.250% Senior Notes due 2030
Debt Instrument [Line Items]
Debt Instrument Redemption Price As Percentage of Principle Amount	101.75%
Twelve Month Period Commencing October 1, 2027 [Member] | 5.250% Senior Notes due 2030
Debt Instrument [Line Items]
Debt Instrument Redemption Price As Percentage of Principle Amount	100.875%
Twelve Month Period Commencing October 1, 2028 [Member] | 5.250% Senior Notes due 2030
Debt Instrument [Line Items]
Debt Instrument Redemption Price As Percentage of Principle Amount	100.00%
Twelve month period commencing on April 15, 2022 [Member] | 8.125% Notes Due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument Redemption Price As Percentage of Principle Amount		104.063%
Twelve Month Period Commencing April 15, 2023 [Member] | 8.125% Notes Due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument Redemption Price As Percentage of Principle Amount		102.031%
Twelve month period commencing on April 15, 2024 [Member] | 8.125% Notes Due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument Redemption Price As Percentage of Principle Amount		100.00%
NCR International, Inc. [Member] | Guarantor Subsidiaries [Member]
Debt Instrument [Line Items]
Subsidiary or Equity Method Investee, Cumulative Percentage Ownership after All Transactions			100.00%
NCR International, Inc. [Member] | Guarantor Subsidiaries [Member] | 5.00% Senior Notes due 2022
Debt Instrument [Line Items]
Debt stated interest rate			5.00%
NCR International, Inc. [Member] | Guarantor Subsidiaries [Member] | 6.375% Senior Notes due 2023
Debt Instrument [Line Items]
Debt stated interest rate			6.375%
NCR International, Inc. [Member] | Guarantor Subsidiaries [Member] | 8.125% Notes Due 2025 [Member]
Debt Instrument [Line Items]
Debt stated interest rate			8.125%