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v3.19.3.a.u2

Supplemental Information on Oil and Gas Exploration and Production Activities (Unaudited) Supplemental Information on Oil and Gas Exploration and Production Activities (Unaudited) - Narrative (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 USD ($) Bcfe well $ / bbl $ / MMBTU | Dec. 31, 2018 USD ($) Tcfe Bcfe well $ / bbl $ / MMBTU | Dec. 31, 2017 USD ($) Tcfe Bcfe well $ / bbl $ / MMBTU
Reserve Quantities [Line Items] |  |  |
Interest capitalized | $ | $ 3,372 | $ 4,470 | $ 9,470
Interest cost capitalized, acquisition and development activities | $ | $ 30,100 | $ 37,700 | $ 35,700
Increase (decrease) in reserve during the period | 1,100 | 711.2 |
Proved developed and undeveloped reserve, decrease, percentage | 0.50% |  |
Decline in performance |  |  |
Reserve Quantities [Line Items] |  |  |
Proved developed and undeveloped reserve, revision of previous estimate | 733.8 |  |
Lower commodity prices |  |  |
Reserve Quantities [Line Items] |  |  |
Proved developed and undeveloped reserve, revision of previous estimate | 296.4 |  |
Oil derivatives |  |  |
Reserve Quantities [Line Items] |  |  |
Price per unit (usd per barrel or MMbtu) | $ / bbl | 55.85 | 65.56 | 51.34
Natural gas, per MMbtu |  |  |
Reserve Quantities [Line Items] |  |  |
Price per unit (usd per barrel or MMbtu) | $ / MMBTU | 2.58 | 3.10 | 2.98
Natural gas liquids |  |  |
Reserve Quantities [Line Items] |  |  |
Price per unit (usd per barrel or MMbtu) | $ / bbl | 21.25 | 32.02 | 18.40
SCOOP Properties |  |  |
Reserve Quantities [Line Items] |  |  |
Increase (decrease) in reserve during the period | 302.9 | 90.1 |
Planned unit development | well | 37 | 11 |
Proved developed and undeveloped reserve, purchase of mineral in place | Tcfe |  |  | 1.5
SCOOP Properties | Decline in performance |  |  |
Reserve Quantities [Line Items] |  |  |
Planned unit development | well | 22 |  |
SCOOP Properties | Rescheduled drilling |  |  |
Reserve Quantities [Line Items] |  |  |
Proved undeveloped reserves, postponement of drilling period |  | 5 years |
SCOOP Properties | Exclusion of PUD locations |  |  |
Reserve Quantities [Line Items] |  |  |
Planned unit development | well |  | 12 |
Utica Shale |  |  |
Reserve Quantities [Line Items] |  |  |
Increase (decrease) in reserve during the period | 793.5 | 556.3 | 1.6
Planned unit development | well | 72 | 75 | 10
Proved developed and undeveloped reserves, sale of mineral in place |  | 44.9 |
Utica Shale | Improved performance |  |  |
Reserve Quantities [Line Items] |  |  |
Proved developed and undeveloped reserve, revision of previous estimate |  | (82.4) | (201.3)
Utica Shale | Higher commodity prices |  |  |
Reserve Quantities [Line Items] |  |  |
Proved developed and undeveloped reserve, revision of previous estimate |  |  | (214.1)
Utica Shale | Change in ownership interest |  |  |
Reserve Quantities [Line Items] |  |  |
Proved developed and undeveloped reserve, revision of previous estimate |  | (67.6) | (95.9)
Utica Shale | Increase in pricing |  |  |
Reserve Quantities [Line Items] |  |  |
Proved developed and undeveloped reserve, revision of previous estimate |  | (27.9) |
Utica Shale | Decline in performance |  |  |
Reserve Quantities [Line Items] |  |  |
Proved developed, revision of previous estimate | 90.2 |  |
Planned unit development | well | 9 |  |
Proved developed and undeveloped reserve, revision of previous estimate | 347.2 | (8.3) | (133.0)
Utica Shale | Rescheduled drilling |  |  |
Reserve Quantities [Line Items] |  |  |
Proved developed and undeveloped reserve, revision of previous estimate |  |  | (45.7)
Utica Shale | Lower commodity prices |  |  |
Reserve Quantities [Line Items] |  |  |
Proved developed and undeveloped reserve, revision of previous estimate | Tcfe |  | (1.0) |
Utica Shale | Exclusion of PUD locations |  |  |
Reserve Quantities [Line Items] |  |  |
Planned unit development | well |  | 127 |
Utica Shale | Gulfport | Rescheduled drilling |  |  |
Reserve Quantities [Line Items] |  |  |
Planned unit development | well |  |  | 5
Utica Shale | Third Party | Rescheduled drilling |  |  |
Reserve Quantities [Line Items] |  |  |
Planned unit development | well |  |  | 5
Louisiana Field |  |  |
Reserve Quantities [Line Items] |  |  |
Increase (decrease) in reserve during the period |  | 3.0 |
Planned unit development | well |  | 13 |
Louisiana Field | Rescheduled drilling |  |  |
Reserve Quantities [Line Items] |  |  |
Planned unit development | well |  |  | 2
Proved developed and undeveloped reserve, revision of previous estimate |  |  | (0.6)
Proved undeveloped reserves, postponement of drilling period |  |  | 5 years
Investment in Grizzly Oil Sands ULC |  |  |
Reserve Quantities [Line Items] |  |  |
Equity investment ownership interest | 24.9999% |  |
Oil and gas properties |  |  |
Reserve Quantities [Line Items] |  |  |
Interest capitalized | $ | $ 3,400 | $ 4,500 | $ 9,500

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