Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Income (loss) used in basic and diluted loss per share
Net loss	$ (30.3)	$ (8.1)	$ (23.1)	$ (93.4)	$ (38.4)	$ (116.5)
Net (income) loss attributable to noncontrolling interests	0.0		0.6		0.0	0.0
Net loss attributable to Diebold Nixdorf, Incorporated	$ (30.3)		$ (23.7)		$ (38.4)	$ (116.5)
Denominator
Weighted-average number of common shares used in basic and diluted loss per share (1)	78.3		77.6		78.2	77.4
Net loss attributable to Diebold Nixdorf, Incorporated
Basic and diluted loss per share	$ (0.39)		$ (0.31)		$ (0.49)	$ (1.51)
Anti-dilutive shares
Incremental Shares Excluded From Dilutive Calculation Due To Resulting in Operating Loss	1.3		0.5		1.3	1.0
Anti-dilutive shares not used in calculating diluted weighted-average shares	1.6		3.7		1.6	2.7