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Description Of Business And Significant Accounting Policies (Accounts Receivable) (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
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Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Accounts receivable - current | $ 557 | $ 533
Revenue [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Accounts receivable - current | 415 | 396
Tax [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Accounts receivable - current | 65 | 129
Accounts receivable - noncurrent | 65 | 130
Joint Interest [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Accounts receivable - current | $ 77 | $ 8

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- Definition Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4531-111522 + Details
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