v3.19.1
INCOME TAXES (Reconciliation of Statutory Rate) (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Income Tax Disclosure [Abstract]      
Federal taxes at statutory rate $ 2,497 $ (8,873) $ (22,941)
State taxes, net of federal benefit 1,663 (1,414) (4,982)
Change in valuation allowance (3,330) (104,710) 24,522
Change in federal and state tax rate 634 115,545  
Percentage depletion (656) (598) (552)
Other (700) (2,733) 2,591
Total income tax expense (benefit) $ 108 $ (2,783) $ (1,362)
Effective tax rate 0.90% 11.00% 2.10%