Acquisitions and Divestitures (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Assets			$ (7.6)	$ 6.7	$ (1.0)
Percentage of net divestiture sales of total net sales (less than)			1.00%	1.00%	1.00%
Payments for Repurchase of Redeemable Noncontrolling Interest			$ 89.2	$ 345.2	$ 3.5
Payments to Acquire Businesses, Net of Cash Acquired			0.0	$ 5.9	5.6
Projective N.V. [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Assets			2.8
Proceeds from Divestiture of Businesses			4.2
Legacy Diebold United Kingdom [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Assets					2.2
Proceeds from Divestiture of Businesses					5.0
Venezuela Business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Assets			(4.1)
Netherlands Entities [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Assets	$ 3.5
SecurCash B.V. [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Assets			(1.1)
Proceeds from Divestiture of Businesses			0.6
Eurasia Banking Entity [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Assets			(0.1)
Kony Inc [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Assets			7.3
Proceeds from Divestiture of Businesses			21.3
Diebold Nixdorf AG China Subsidiaries [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Payments for Repurchase of Redeemable Noncontrolling Interest			97.5
Payments to Acquire Businesses, Net of Cash Acquired		$ 5.8
Moxx and Visio [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired					$ 5.6
Kony, Inc. [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cost Method Investments			$ 14.0			$ 14.0