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Oil And Gas Properties (Narrative) (Q3) (Details) - USD ($) | 9 Months Ended | 12 Months Ended
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Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019 | Dec. 31, 2018
Oil And Gas Properties [Abstract] |  |  |  |
Depletion expense | $ 405,000 | $ 504,000 | $ 637,000 | $ 722,000
Gain (loss) on asset retirement obligations |  | $ 4,000 |  |

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- Definition Gain (Loss) On Asset Retirement Obligation + References No definition available. + Details
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- References No definition available. + Details
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- Definition The noncash expense charged against earnings to recognize the consumption of oil and gas reserves that are part of an entities' assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
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