Quarterly report pursuant to Section 13 or 15(d)

Note 10 - Leases (Details Textual)

v3.8.0.1
Note 10 - Leases (Details Textual) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Dec. 31, 2017
Operating Leases, Rent Expense, Net, Total $ 0.3 $ 0.2  
Pump Assets [Member]      
Capital Leased Assets, Gross, Total 14.0   $ 14.0
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Accumulated Depreciation $ 6.6   $ 6.1
Capital Leases [Member]      
Debt, Weighted Average Interest Rate 3.70%