Annual report pursuant to Section 13 and 15(d)

Environmental Compliance Costs (Details)

v3.8.0.1
Environmental Compliance Costs (Details)
Dec. 31, 2017
USD ($)
solid_waste_management_units
Dec. 31, 2016
USD ($)
Environmental Exit Cost [Line Items]    
Environmental remediation reserves $ 549,000 $ 589,887
Augusta Plant [Member]    
Environmental Exit Cost [Line Items]    
Environmental remediation reserves 474,000 514,887
Bristol, Tennessee Facility [Member]    
Environmental Exit Cost [Line Items]    
Environmental remediation reserves $ 75,000 $ 75,000
Number of solid waste management units | solid_waste_management_units 2