Quarterly report pursuant to Section 13 or 15(d)

Equity Investments (Investments Accounted for by the Equity Method) (Details)

v3.8.0.1
Equity Investments (Investments Accounted for by the Equity Method) (Details) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Dec. 31, 2016
Feb. 29, 2016
Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]              
Equity investments and investments in subsidiaries $ 279,282   $ 279,282   $ 243,920    
(Income) loss from equity method investments $ 2,737 $ (5,997) $ 20,945 $ 25,576      
Investment in Tatex Thailand II, LLC              
Schedule of Equity Method Investments [Line Items]              
Approximate ownership % 23.50%   23.50%        
Equity investments and investments in subsidiaries $ 0   $ 0   0    
(Income) loss from equity method investments $ (95) (253) $ (549) (412)      
Investment in Tatex Thailand III, LLC              
Schedule of Equity Method Investments [Line Items]              
Approximate ownership % 17.90%   17.90%        
Equity investments and investments in subsidiaries $ 0   $ 0   0    
(Income) loss from equity method investments $ 0 0 $ 0 0      
Investment in Grizzly Oil Sands ULC              
Schedule of Equity Method Investments [Line Items]              
Approximate ownership % 24.9999%   24.9999%        
Equity investments and investments in subsidiaries $ 58,674   $ 58,674   45,213    
(Income) loss from equity method investments $ 296 363 $ 869 24,811      
Investment in Timber Wolf Terminals LLC              
Schedule of Equity Method Investments [Line Items]              
Approximate ownership % 50.00%   50.00%        
Equity investments and investments in subsidiaries $ 983   $ 983   991    
(Income) loss from equity method investments $ 4 3 $ 8 7      
Investment in Windsor Midstream LLC              
Schedule of Equity Method Investments [Line Items]              
Approximate ownership % 22.50%   22.50%        
Equity investments and investments in subsidiaries $ 31   $ 31   25,749    
(Income) loss from equity method investments $ (2) (9,014) $ 25,232 (12,062)      
Investment in Stingray Cementing LLC              
Schedule of Equity Method Investments [Line Items]              
Approximate ownership % 0.00%   0.00%        
Equity investments and investments in subsidiaries $ 0   $ 0   1,920    
(Income) loss from equity method investments $ 0 79 $ 205 187      
Investment in Blackhawk Midstream LLC              
Schedule of Equity Method Investments [Line Items]              
Approximate ownership % 48.50%   48.50%        
Equity investments and investments in subsidiaries $ 0   $ 0   0    
(Income) loss from equity method investments $ 0 0 $ 0 0      
Investment in Stingray Energy Services LLC              
Schedule of Equity Method Investments [Line Items]              
Approximate ownership % 0.00%   0.00%        
Equity investments and investments in subsidiaries $ 0   $ 0   4,215    
(Income) loss from equity method investments $ 0 294 $ 282 935      
Investment in Sturgeon Acquisitions LLC              
Schedule of Equity Method Investments [Line Items]              
Approximate ownership % 0.00%   0.00%       25.00%
Equity investments and investments in subsidiaries $ 0   $ 0   20,526    
(Income) loss from equity method investments $ 0 112 $ (71) 623      
Investment in Mammoth Energy Services, Inc.              
Schedule of Equity Method Investments [Line Items]              
Approximate ownership % 25.10%   25.10%        
Equity investments and investments in subsidiaries $ 149,219   $ 149,219   111,717    
(Income) loss from equity method investments $ 2,407 2,518 $ (7,616) 11,527      
Investment in Strike Force Midstream LLC              
Schedule of Equity Method Investments [Line Items]              
Approximate ownership % 25.00%   25.00%     25.00%  
Equity investments and investments in subsidiaries $ 70,375   $ 70,375   $ 33,589    
(Income) loss from equity method investments $ 127 $ (99) $ 2,585 $ (40)