Equity (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Balance	$ (863.5)	$ (842.6)	$ (840.0)	$ (811.7)	$ (708.5)	$ (710.6)	$ (863.5)	$ (811.7)
Net loss attributable to Diebold Nixdorf, Incorporated	(2.1)			(101.4)			(40.5)	(217.9)
Net loss	(2.0)	(30.3)	(8.1)	(100.9)	(23.1)	(93.4)	(40.4)	(217.4)
Other comprehensive loss	(23.5)	23.4	(30.4)	(5.7)	45.1	(105.5)	(30.5)	(66.1)
Share-based compensation issued	0.0	0.0	0.0	(0.1)	0.0	0.0
Share-based compensation expense	4.6	4.5	3.5	3.5	3.6	4.0
Treasury shares	0.0	(0.2)	(5.2)		(0.1)	(4.6)
Reclassifications of redeemable noncontrolling interest			31.9
Divestitures, net	0.0	0.0			(23.4)	(4.8)
Balance	(842.6)	(840.0)	(831.7)	(708.5)	(710.6)	(506.3)	(831.7)	(506.3)
Common Stock [Member]
Balance	118.2	118.2	118.0	116.9	116.9	116.7	118.2	116.9
Share-based compensation issued	0.0	(0.2)	(1.1)	0.0	(0.2)	(1.4)
Balance	118.2	118.0	116.9	116.9	116.7	115.3	116.9	115.3
Additional Paid-in Capital [Member]
Balance	818.4	813.8	809.5	783.3	779.9	776.5	818.4	783.3
Share-based compensation issued	0.0	(0.2)	(1.1)	(0.1)	(0.2)	(1.4)
Share-based compensation expense	4.6	4.5	3.5	3.5	3.6	4.0
Reclassifications of redeemable noncontrolling interest			19.2
Balance	813.8	809.5	787.9	779.9	776.5	773.9	787.9	773.9
Retained Earnings [Member]
Balance	(782.8)	(780.7)	(750.4)	(690.2)	(588.8)	(565.1)	(782.8)	(690.2)
Net loss attributable to Diebold Nixdorf, Incorporated	(2.1)	(30.3)	(8.1)	(101.4)	(23.7)	(92.8)	(40.5)	(217.9)
Balance	(780.7)	(750.4)	(742.3)	(588.8)	(565.1)	(472.3)	(742.3)	(472.3)
Treasury Stock [Member]
Balance	(582.1)	(582.1)	(581.9)	(576.6)	(576.6)	(576.5)	(582.1)	(576.6)
Treasury shares	0.0	(0.2)	(5.2)		(0.1)	(4.6)
Balance	(582.1)	(581.9)	(576.7)	(576.6)	(576.5)	(571.9)	(576.7)	(571.9)
AOCI Attributable to Parent
Balance	(444.0)	(420.5)	(443.8)	(440.0)	(434.4)	(479.5)	(444.0)	(440.0)
Other comprehensive loss	(23.5)	23.3	(30.9)	(5.6)	45.1	(104.2)
Balance	(420.5)	(443.8)	(412.9)	(434.4)	(479.5)	(375.3)	(412.9)	(375.3)
Parent [Member]
Balance	(872.3)	(851.3)	(848.6)	(806.6)	(703.0)	(727.9)	(872.3)	(806.6)
Net loss attributable to Diebold Nixdorf, Incorporated	(2.1)	(30.3)	(8.1)	(101.4)	(23.7)	(92.8)
Other comprehensive loss	(23.5)	23.3	(30.9)	(5.6)	45.1	(104.2)
Share-based compensation issued	0.0			(0.1)	0.0	0.0
Share-based compensation expense	4.6	4.5	3.5	3.5	3.6	4.0
Treasury shares	0.0	(0.2)	(5.2)		(0.1)	(4.6)
Reclassifications of redeemable noncontrolling interest			19.2
Divestitures, net					0.0	0.0
Balance	(851.3)	(848.6)	(827.1)	(703.0)	(727.9)	(530.3)	(827.1)	(530.3)
Noncontrolling Interest [Member]
Balance	8.8	8.7	8.6	(5.1)	(5.5)	17.3	8.8	(5.1)
Net loss	0.1	0.0	0.0	0.5	0.6	(0.6)
Other comprehensive loss	0.0	0.1	0.5	(0.1)	0.0	(1.3)
Reclassifications of redeemable noncontrolling interest			12.7
Divestitures, net	0.0	0.0			(23.4)	(4.8)
Balance	$ 8.7	$ 8.6	$ (4.6)	$ (5.5)	$ 17.3	$ 24.0	$ (4.6)	$ 24.0