Quarterly report pursuant to Section 13 or 15(d)

EQUITY INVESTMENTS (Narrative) (Details)

v3.20.1
EQUITY INVESTMENTS (Narrative) (Details)
$ / shares in Units, a in Thousands
 3 Months Ended
Mar. 31, 2020
USD ($)
a
$ / shares
shares
Mar. 31, 2019
USD ($)
Dec. 31, 2019
USD ($)
Jun. 30, 2019
Schedule of Equity Method Investments [Line Items]        
Equity investments $ 6,225,000   $ 32,044,000  
Investment in Mammoth Energy Services, Inc.        
Schedule of Equity Method Investments [Line Items]        
Equity method investment, ownership (in shares) | shares 9,829,548      
Share dividend (in usd per share) | $ / shares $ 0.125      
Approximate fair value, quoted market price $ 7,400,000      
Investment in Mammoth Energy Services, Inc.        
Schedule of Equity Method Investments [Line Items]        
Equity method investment, ownership interest, percent 21.50%      
Equity method investments, increase (decrease) due to foreign currency translation adjustment $ (400,000) $ 100,000    
Distributions from equity method investments 0 1,200,000    
Equity investments $ 0   11,005,000  
Investment in Grizzly Oil Sands ULC        
Schedule of Equity Method Investments [Line Items]        
Equity method investment, ownership interest, percent 24.90%      
Equity method investment, impairment $ 0 0    
Equity method investment, amount of cash calls, based on proportionate ownership interest   400,000    
Equity method investments, increase (decrease) due to foreign currency translation adjustment (14,700,000) 3,700,000    
Equity investments $ 6,186,000   21,000,000  
Windsor Midstream LLC        
Schedule of Equity Method Investments [Line Items]        
Equity method investment, ownership interest, percent 22.50%      
Distributions from equity method investments $ 0      
Equity investments $ 39,000   39,000  
Tatex Thailand II, LLC        
Schedule of Equity Method Investments [Line Items]        
Equity method investment, ownership interest, percent 23.50%      
Distributions from equity method investments $ 0 $ 100,000    
Equity investments $ 0   $ 0  
Athabasca, Peace River And Cold Lake Oil Sands Regions | Investment in Grizzly Oil Sands ULC        
Schedule of Equity Method Investments [Line Items]        
Gas and oil area, reserve (in acres) | a 830      
Phu Horm Field | Apico Llc        
Schedule of Equity Method Investments [Line Items]        
Gas and oil area, reserve (in acres) | a 108      
Apico Llc | Tatex Thailand II, LLC        
Schedule of Equity Method Investments [Line Items]        
Ownership percentage       8.50%