Contingencies - Narrative (Details) - USD ($) $ in Millions	Jun. 09, 2015	Mar. 31, 2020
Loss Contingencies [Line Items]
Loss Contingency, Receivable		$ 16.5
Accrued liabilities
Loss Contingencies [Line Items]
Loss Contingency Accrual		21.0
Highway Products Litigation | False Claims Act, USA
Loss Contingencies [Line Items]
Total amount of judgment entered by the District Court	$ 682.4
Highway Products Litigation | State, county, and municipal actions
Loss Contingencies [Line Items]
Loss Contingency Accrual		0.0
Class Action, Shareholder | Class Action, Shareholder
Loss Contingencies [Line Items]
Loss Contingency Accrual		7.5
Environmental and workplace matters
Loss Contingencies [Line Items]
Loss Contingency Accrual		1.3
Minimum
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss		19.3
Maximum
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss		$ 32.5