Quarterly report pursuant to Section 13 or 15(d)

Notes Payable and Revolving Credit Facility (Scheduled Principal Payments Due On West Mifflin Note Payable) (Details)

v3.8.0.1
Notes Payable and Revolving Credit Facility (Scheduled Principal Payments Due On West Mifflin Note Payable) (Details) - West Mifflin Note Payable [Member] - USD ($)
Mar. 31, 2018
Dec. 31, 2017
Sep. 25, 2015
Debt Instrument [Line Items]      
2019 $ 136,000    
2020 7,220,000    
Total $ 7,378,000 $ 7,378,000 $ 7,378