Supplemental Guarantor Information (Condensed Consolidating Balance Sheet) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
Due to Affiliate, Noncurrent		$ 0.0
Cash, cash equivalents and restricted cash	$ 446.4	280.9
Short-term investments	9.0	10.0
Trade receivables, net	588.8	619.3
Intercompany receivables	0.0	0.0
Inventories	513.4	466.5
Prepaid, income taxes and other current assets	337.8	515.3
Total current assets	1,895.4	1,892.0
Securities and other investments	17.4	21.4
Property, plant and equipment, net	205.5	231.5
Goodwill	775.1	764.0		$ 798.2
Deferred income taxes	135.3	120.8
Customer relationships, net	454.1	502.3
Investment in subsidiary	0.0	0.0
Long-term intercompany receivables	0.0
Other assets	283.2	313.2
Assets	3,721.1	3,790.6
Current liabilities
Notes payable	102.1	32.5
Accounts payable	479.6	471.5
Intercompany payable	0.0	0.0
Deferred revenue	300.6	320.5
Payroll and other benefits liabilities	161.0	224.7
Other current liabilities	484.6	550.4
Total current liabilities	1,527.9	1,599.6
Long-term debt	2,362.4	2,108.7
Pensions, post-retirement and other benefits	231.1	237.7
Long-term intercompany payable	0.0	0.0
Other long-term liabilities	519.2	330.0
Redeemable noncontrolling interests	20.1	20.9	$ 21.7	$ 130.4
Total Diebold Nixdorf, Incorporated shareholders' equity	(703.0)	(530.3)
Noncontrolling interests	(5.5)	24.0
Total liabilities, redeemable noncontrolling interests and equity	3,721.1	3,790.6
Reportable Legal Entities [Member] | Parent Company [Member]
Due to Affiliate, Noncurrent		0.0
Cash, cash equivalents and restricted cash	194.5	3.6
Short-term investments	0.0	0.0
Trade receivables, net	122.4	109.0
Intercompany receivables	600.0	632.6
Inventories	115.3	122.4
Prepaid, income taxes and other current assets	20.1	42.1
Total current assets	1,052.3	909.7
Securities and other investments	17.4	21.4
Property, plant and equipment, net	52.0	61.9
Goodwill	55.5	55.5
Deferred income taxes	71.8	51.1
Investment in subsidiary	1,589.6	1,676.8
Long-term intercompany receivables	615.9
Other assets	52.0	64.3
Assets	3,506.5	3,458.6
Current liabilities
Notes payable	93.2	26.6
Accounts payable	81.4	55.3
Intercompany payable	1,220.0	1,302.3
Deferred revenue	107.5	133.7
Payroll and other benefits liabilities	44.6	49.4
Other current liabilities	96.7	109.5
Total current liabilities	1,643.4	1,676.8
Long-term debt	2,360.7	2,107.4
Pensions, post-retirement and other benefits		160.3
Long-term intercompany payable	0.0	617.9
Other long-term liabilities	205.4	42.7
Redeemable noncontrolling interests	0.0	0.0
Total Diebold Nixdorf, Incorporated shareholders' equity	(703.0)	(528.6)
Noncontrolling interests	0.0	0.0
Total liabilities, redeemable noncontrolling interests and equity	3,506.5	3,458.6
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Due to Affiliate, Noncurrent		0.0
Cash, cash equivalents and restricted cash	0.0	1.8
Short-term investments	0.0	0.0
Trade receivables, net	0.1	0.0
Intercompany receivables	549.8	559.3
Inventories	0.0	0.0
Prepaid, income taxes and other current assets	7.9	7.8
Total current assets	557.8	568.9
Securities and other investments	0.0	0.0
Property, plant and equipment, net	0.0	0.5
Goodwill	0.0	0.0
Deferred income taxes	6.4	6.4
Investment in subsidiary	0.0	0.0
Long-term intercompany receivables	0.0
Other assets	3.4	0.1
Assets	567.6	575.9
Current liabilities
Notes payable	0.0	0.0
Accounts payable	0.0	0.0
Intercompany payable	45.2	46.7
Deferred revenue	0.0	0.0
Payroll and other benefits liabilities	0.0	2.1
Other current liabilities	0.9	1.0
Total current liabilities	46.1	49.8
Long-term debt	0.0	0.0
Pensions, post-retirement and other benefits		0.0
Long-term intercompany payable	0.0	0.0
Other long-term liabilities	0.0	0.0
Redeemable noncontrolling interests	0.0	0.0
Total Diebold Nixdorf, Incorporated shareholders' equity	521.5	526.1
Noncontrolling interests	0.0	0.0
Total liabilities, redeemable noncontrolling interests and equity	567.6	575.9
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Due to Affiliate, Noncurrent		617.9
Cash, cash equivalents and restricted cash	251.9	275.5
Short-term investments	9.0	10.0
Trade receivables, net	466.3	510.3
Intercompany receivables	670.2	747.6
Inventories	403.0	346.4
Prepaid, income taxes and other current assets	317.6	473.2
Total current assets	2,118.0	2,363.0
Securities and other investments	0.0	0.0
Property, plant and equipment, net	153.5	169.1
Goodwill	719.6	708.5
Deferred income taxes	57.1	63.3
Investment in subsidiary	0.0	0.0
Long-term intercompany receivables	0.0
Other assets	227.8	248.8
Assets	3,685.2	4,000.4
Current liabilities
Notes payable	8.9	5.9
Accounts payable	398.2	416.2
Intercompany payable	554.8	590.5
Deferred revenue	193.1	186.8
Payroll and other benefits liabilities	116.4	173.2
Other current liabilities	394.8	447.7
Total current liabilities	1,666.2	1,820.3
Long-term debt	1.7	1.3
Pensions, post-retirement and other benefits		77.4
Long-term intercompany payable	615.9	0.0
Other long-term liabilities	313.8	287.3
Redeemable noncontrolling interests	20.1	20.9
Total Diebold Nixdorf, Incorporated shareholders' equity	1,073.0	1,151.3
Noncontrolling interests	(5.5)	24.0
Total liabilities, redeemable noncontrolling interests and equity	3,685.2	4,000.4
Consolidation, Eliminations [Member]
Due to Affiliate, Noncurrent		(617.9)
Cash, cash equivalents and restricted cash	0.0	0.0
Short-term investments	0.0	0.0
Trade receivables, net	0.0	0.0
Intercompany receivables	(1,820.0)	(1,939.5)
Inventories	(4.9)	(2.3)
Prepaid, income taxes and other current assets	(7.8)	(7.8)
Total current assets	(1,832.7)	(1,949.6)
Securities and other investments	0.0	0.0
Property, plant and equipment, net	0.0	0.0
Goodwill	0.0	0.0
Deferred income taxes	0.0	0.0
Investment in subsidiary	(1,589.6)	(1,676.8)
Long-term intercompany receivables	(615.9)
Other assets	0.0	0.0
Assets	(4,038.2)	(4,244.3)
Current liabilities
Notes payable	0.0	0.0
Accounts payable	0.0	0.0
Intercompany payable	(1,820.0)	(1,939.5)
Deferred revenue	0.0	0.0
Payroll and other benefits liabilities	0.0	0.0
Other current liabilities	(7.8)	(7.8)
Total current liabilities	(1,827.8)	(1,947.3)
Long-term debt	0.0	0.0
Pensions, post-retirement and other benefits		0.0
Long-term intercompany payable	(615.9)	(617.9)
Other long-term liabilities	0.0	0.0
Redeemable noncontrolling interests	0.0	0.0
Total Diebold Nixdorf, Incorporated shareholders' equity	(1,594.5)	(1,679.1)
Noncontrolling interests	0.0	0.0
Total liabilities, redeemable noncontrolling interests and equity	(4,038.2)	(4,244.3)
Customer Relationships [Member]
Customer relationships, net	409.2	447.7
Customer Relationships [Member] | Reportable Legal Entities [Member] | Parent Company [Member]
Customer relationships, net	0.0	0.0
Customer Relationships [Member] | Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Customer relationships, net	0.0	0.0
Customer Relationships [Member] | Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Customer relationships, net	409.2	447.7
Customer Relationships [Member] | Consolidation, Eliminations [Member]
Customer relationships, net	$ 0.0	$ 0.0