Commitments and Contingencies (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
ACP [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	$ 1.0
ACP [Member] | Minimum [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	0.1
SB Decking [Member]
Loss Contingencies [Line Items]
Loss Contingency Accrual At Carrying Value	0.4
Houghton Environmental Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency Accrual At Carrying Value	5.7	$ 6.0
Houghton Environmental Matters [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	6.0
Houghton Environmental Matters [Member] | Minimum [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	5.0
Other Environmental Matters [Member]
Loss Contingencies [Line Items]
Loss Contingency Accrual At Carrying Value	0.1	$ 0.1
Foreign Consumption Tax [Member]
Loss Contingencies [Line Items]
Loss Contingency Accrual At Carrying Value	1.7
Business Combination Indemnification Assets Amount As Of Acquisition Date	22.0
OtherAssetsMiscellaneousCurrent	1.1
IncomeTaxReconciliationTaxSettlementsForeign	10.0
Foreign Consumption Tax [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	38.0
Foreign Consumption Tax [Member] | Minimum [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	$ 0.6