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Basis of Presentation (Details) $ in Millions	3 Months Ended		6 Months Ended
Basis of Presentation (Details) $ in Millions	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) segment	Jun. 30, 2019 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of reportable segments \| segment			1
Net income (loss) from discontinued operations	$ 1.1	$ (0.3)	$ 1.0	$ (0.6)
Inventory Purchases \| Immediate Family Member of Management or Principal Owner
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Purchases from related party			1.8
Expenses from transaction with related party			0.5
Related party accounts payable	0.1		0.1
Revenue from related party			0.3
Discontinued Operations - Disposed of by Sale \| NATG
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net income (loss) from discontinued operations	$ 1.1	$ (0.3)	$ 1.0	$ (0.6)