Quarterly report pursuant to Section 13 or 15(d)

COMMITMENTS AND CONTINGENCIES (Narrative) (Details)

v3.20.2
COMMITMENTS AND CONTINGENCIES (Narrative) (Details)
MMBTU in Thousands, $ in Thousands
1 Months Ended 3 Months Ended 6 Months Ended
Jun. 30, 2020
USD ($)
MMBTU
Apr. 15, 2019
violation
Jan. 04, 2017
violation
Dec. 11, 2013
Apr. 30, 2020
Oct. 31, 2018
USD ($)
Jun. 30, 2020
USD ($)
MMBTU
Jun. 30, 2019
USD ($)
Jun. 30, 2020
USD ($)
MMBTU
complaint
Jun. 30, 2019
USD ($)
Commitments [Line Items]                    
Number of claims filed (in claims) | complaint                 2  
Loss contingency, damages sought $ 28,000                  
Loss contingency, damages sought, percentages of unpaid overtime compensation         6.00%          
FOVs (in sites)   1 1 1         17  
Loss contingency accrual $ 1,700           $ 1,700   $ 1,700  
Environmental cost           $ 180        
Transportation commitment                    
Commitments [Line Items]                    
Firm transportation contracts, remainder of 2020 and 2021 | MMBTU 1,455           1,455   1,455  
Loss on long-term purchase commitment | Muskie Proppant LLC                    
Commitments [Line Items]                    
Non-utilization fees, accrued damages year to date             $ 1,900 $ 300 $ 3,800 $ 300