Commitments and Contingencies - Narrative (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Loss Contingencies [Line Items]
Unrelated Environmental Liability Accruals	$ 200,000	$ 200,000
ACP [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	1,000,000
ACP [Member] | Minimum [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	100,000
SB Decking [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	$ 1,700,000