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Supplemental Oil And Gas Information (Narrative) (Details) | 12 Months Ended
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Dec. 31, 2019 USD ($) item $ / bbl | Dec. 31, 2018 item $ / bbl | Dec. 31, 2017 item $ / bbl
Oil and Gas, Average Sale Price and Production Cost Per Unit [Line Items] |  |  |
Proved undeveloped reserve locations | item | 0 | 7 | 3
Depreciation, depletion, or any indirect cost | $ | $ 0 |  |
Barrel Of Oil [Member] |  |  |
Oil and Gas, Average Sale Price and Production Cost Per Unit [Line Items] |  |  |
Price | $ / bbl | 50.65 | 60.21 | 45.83

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- Definition Sales price per unit of oil and gas produced. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1204 -Paragraph (b) -Subparagraph (1) + Details
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- Definition Depreciation, depletion, amortization, and accretion related to oil and gas producing activities. + References No definition available. + Details
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- Details
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