Annual report pursuant to Section 13 and 15(d)

Derivatives and Fair Value (Narrative) (Details)

v3.20.4
Derivatives and Fair Value (Narrative) (Details)
Jan. 22, 2021
$ / bbl
bbl
May 06, 2019
$ / bbl
bbl
Jun. 30, 2018
bbl
$ / bbl
Commodity Contract, June 2018 Through June 2019 [Member]      
Derivative Instruments and Hedging Activities Disclosures [Line Items]      
Derivative, average price per barrel | $ / bbl     74.00
Derivative, nonmonetary notional amount | bbl     400,000
Commodity Contract, July 19 Through June 2020 [Member]      
Derivative Instruments and Hedging Activities Disclosures [Line Items]      
Derivative, average price per barrel | $ / bbl   66.70  
Barrels | bbl   500,000  
Subsequent Event [Member] | Commodity Contract, February 2021 Through January 2022 [Member]      
Derivative Instruments and Hedging Activities Disclosures [Line Items]      
Derivative, average price per barrel | $ / bbl 53.10    
Barrels | bbl 709,262