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Description Of Business And Significant Accounting Policies (Narrative) (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Description Of Business And Significant Accounting Policies [Line Items] |  |  |
Material natural gas imbalances | $ 0 | $ 0 |
Methane gas revenue | 0 | 0 |
Impairment of equipment and materials inventory |  | 88,000 |
Unevaluated properties | $ 0 | 106,000 |
Current cost discount | 10.00% |  |
Stock based compensation | $ 14,000 | 17,000 | $ 12,000
Federal net operating loss carryforwards | 30,200,000 |  |
Deferred tax asset | $ 242,000 |  |
Shares excluded from dilutive shares |  | 114 | 760
Customer A [Member] | Revenue [Member] |  |  |
Description Of Business And Significant Accounting Policies [Line Items] |  |  |
Customer's percentage of revenue | 75.30% | 73.90% | 74.50%
Customer B [Member] | Revenue [Member] |  |  |
Description Of Business And Significant Accounting Policies [Line Items] |  |  |
Customer's percentage of revenue | 13.10% | 13.10% | 16.10%
Customer C [Member] | Revenue [Member] |  |  |
Description Of Business And Significant Accounting Policies [Line Items] |  |  |
Customer's percentage of revenue | 11.00% | 12.00% | 8.60%
Two Customers [Member] | Accounts Receivable [Member] |  |  |
Description Of Business And Significant Accounting Policies [Line Items] |  |  |
Customer's percentage of revenue | 76.20% | 84.10% |
Customer D [Member] | Accounts Receivable [Member] |  |  |
Description Of Business And Significant Accounting Policies [Line Items] |  |  |
Customer's percentage of revenue | 63.20% | 71.00% |
Minimum [Member] |  |  |
Description Of Business And Significant Accounting Policies [Line Items] |  |  |
Federal net operating loss carryforwards expiration between, years | Dec. 31, 2019 |  |
Maximum [Member] |  |  |
Description Of Business And Significant Accounting Policies [Line Items] |  |  |
Federal net operating loss carryforwards expiration between, years | Dec. 31, 2036 |  |

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