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)

v3.10.0.1
Notes Payable and Revolving Credit Facility (Scheduled Principal Payments Due On West Mifflin Note Payable) (Details) - West Mifflin Note Payable [Member] - USD ($)
$ in Thousands
Jun. 30, 2018
Dec. 31, 2017
Sep. 25, 2015
Debt Instrument [Line Items]      
2018 $ 22    
2019 136    
2020 7,220    
Total $ 7,378 $ 7,378 $ 7,378