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Description Of Business And Significant Accounting Policies (Accounts Receivable) (Q3) (Details) - USD ($) | Sep. 30, 2020 | Mar. 27, 2020 | Dec. 31, 2019 | Dec. 31, 2018
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Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Accounts receivable - current | $ 262,000 |  | $ 557,000 | $ 533,000
Revenue [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Accounts receivable - current | 259,000 |  | 415,000 | 396,000
Tax [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Accounts receivable - current |  | $ 65,000 | 65,000 | 129,000
Accounts receivable - noncurrent |  |  | 65,000 | 130,000
Joint Interest [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Accounts receivable - current | $ 3,000 |  | $ 77,000 | $ 8,000

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