Quarterly report pursuant to Section 13 or 15(d)

Derivative Instruments and Hedging Activities (Schedule of Derivative Instruments in Statement of Financial Position, Fair Value) (Details)

v3.21.1
Derivative Instruments and Hedging Activities (Schedule of Derivative Instruments in Statement of Financial Position, Fair Value) (Details) - Not Designated as Hedging Instrument - USD ($)
$ in Thousands
Mar. 31, 2021
Dec. 31, 2020
Other current assets    
Offsetting Assets and Liabilities [Line Items]    
Presented without Effects of Netting $ 74,848 $ 21,156
Effects of Netting (69,352) (20,235)
As Presented with Effects of Netting 5,496 921
Other current assets | Contingent consideration arrangements    
Offsetting Assets and Liabilities [Line Items]    
Presented without Effects of Netting 5,375 0
Effects of Netting 0 0
As Presented with Effects of Netting 5,375 0
Other current assets | Commodity derivative instruments    
Offsetting Assets and Liabilities [Line Items]    
Presented without Effects of Netting 69,473 21,156
Effects of Netting (69,352) (20,235)
As Presented with Effects of Netting 121 921
Other assets, net    
Offsetting Assets and Liabilities [Line Items]    
Presented without Effects of Netting 3,790 1,816
Effects of Netting (3,351) 0
As Presented with Effects of Netting 439 1,816
Other assets, net | Contingent consideration arrangements    
Offsetting Assets and Liabilities [Line Items]    
Presented without Effects of Netting 0 1,816
Effects of Netting 0 0
As Presented with Effects of Netting 0 1,816
Other assets, net | Commodity derivative instruments    
Offsetting Assets and Liabilities [Line Items]    
Presented without Effects of Netting 3,790 0
Effects of Netting (3,351) 0
As Presented with Effects of Netting 439 0
Fair value of derivatives - current    
Offsetting Assets and Liabilities [Line Items]    
Presented without Effects of Netting (293,798) (117,295)
Effects of Netting 69,352 20,235
As Presented with Effects of Netting (224,446) (97,060)
Fair value of derivatives - current | Contingent consideration arrangements    
Offsetting Assets and Liabilities [Line Items]    
Presented without Effects of Netting (17,913) 0
Effects of Netting 0 0
As Presented with Effects of Netting (17,913) 0
Fair value of derivatives - current | Commodity derivative instruments    
Offsetting Assets and Liabilities [Line Items]    
Presented without Effects of Netting (275,885) (117,295)
Effects of Netting 69,352 20,235
As Presented with Effects of Netting (206,533) (97,060)
Financial guarantee contracts, deferred premium 14,100 11,200
Fair value of derivatives - non-current    
Offsetting Assets and Liabilities [Line Items]    
Presented without Effects of Netting (4,751) (88,046)
Effects of Netting 3,351 0
As Presented with Effects of Netting (1,400) (88,046)
Fair value of derivatives - non-current | Contingent consideration arrangements    
Offsetting Assets and Liabilities [Line Items]    
Presented without Effects of Netting 0 (8,618)
Effects of Netting 0 0
As Presented with Effects of Netting 0 (8,618)
Fair value of derivatives - non-current | Commodity derivative instruments    
Offsetting Assets and Liabilities [Line Items]    
Presented without Effects of Netting (4,751) 0
Effects of Netting 3,351 0
As Presented with Effects of Netting (1,400) 0
Financial guarantee contracts, deferred premium $ 900  
Fair value of derivatives - non-current | September 2020 Warrants liability    
Offsetting Assets and Liabilities [Line Items]    
Presented without Effects of Netting   (79,428)
Effects of Netting   0
As Presented with Effects of Netting   $ (79,428)