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Supplemental Oil And Gas Information (Schedule Of Reserve Value By Category And The Respective Present Values, Before Income Taxes, Discounted At 10% As A Percentage Of Total Proved Reserves) (FY) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Reserve Quantities [Line Items] |  |  |
Total proved reserves year-end reserve report | $ 8,365 | $ 13,976 | $ 8,170
Proved developed producing reserves (PDP) | $ 7,592 | $ 12,534 | $ 7,065
% of PDP reserves to total proved reserves | 91.00% | 90.00% | 87.00%
Proved developed non-producing reserves | $ 773 | $ 739 | $ 1,082
% of PDNP reserves to total proved reserves | 9.00% | 5.00% | 13.00%
Proved undeveloped reserves (PUD) |  | $ 703 | $ 23
% of PUD reserves to total proved reserves |  | 5.00% |
Oil [Member] |  |  |
Reserve Quantities [Line Items] |  |  |
Total proved reserves year-end reserve report | $ 8,365 | $ 13,976 | $ 8,170
Proved developed producing reserves (PDP) | $ 7,592 | $ 12,534 | $ 7,065
% of PDP reserves to total proved reserves | 91.00% | 90.00% | 87.00%
Proved developed non-producing reserves | $ 773 | $ 739 | $ 1,082
% of PDNP reserves to total proved reserves | 9.00% | 5.00% | 13.00%
Proved undeveloped reserves (PUD) |  | $ 703 | $ 23
% of PUD reserves to total proved reserves |  | 5.00% |
Gas [Member] |  |  |
Reserve Quantities [Line Items] |  |  |
Total proved reserves year-end reserve report |  |  |
Proved developed producing reserves (PDP) |  |  |
% of PDP reserves to total proved reserves |  |  |
Proved developed non-producing reserves |  |  |
% of PDNP reserves to total proved reserves |  |  |
Proved undeveloped reserves (PUD) |  |  |
% of PUD reserves to total proved reserves |  |  |

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