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Supplemental Oil And Gas Information (Tables) | 12 Months Ended
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Dec. 31, 2017
Supplemental Oil And Gas Information [Abstract] |
Schedule Of Capitalized Costs Related To Oil And Gas Producing Activities |
﻿ |  |  |  |  |  |
﻿ |  |  |  |  |  |
﻿ |  | Years Ended December 31,
﻿ |  | 2017 |  | 2016
﻿Proved oil and gas properties |  | $ | 5,704 |  | $ | 5,315
﻿Unproved properties |  |  | — |  |  | 106
﻿Total proved and unproved oil and gas properties |  | $ | 5,704 |  | $ | 5,421
﻿Less accumulated depreciation, depletion and amortization |  |  | (984) |  |  | (196)
﻿Net oil and gas properties |  | $ | 4,720 |  | $ | 5,225
﻿
Schedule Of Oil And Gas Property Acquisition, Exploration And Development |
﻿ |  |  |  |  |  |  |  |  |
﻿ |  |  |  |  |  |  |  |  |
﻿ |  | Years Ended December 31,
﻿ |  | 2017 |  | 2016 |  | 2015
﻿Property acquisitions proved |  | $ | — |  | $ | — |  | $ | —
﻿Property acquisitions unproved |  |  | 93 |  |  | 8 |  |  | 90
﻿Exploration cost |  |  | 69 |  |  | 396 |  |  | 22
﻿Development cost |  |  | — |  |  | — |  |  | 252
﻿Total |  | $ | 162 |  | $ | 404 |  | $ | 364
﻿
Schedule Of Results Of Operations From Oil And Gas Producing Activities |
﻿ |  |  |  |  |  |  |  |  |
﻿ |  |  |  |  |  |  |  |  |
﻿ |  | Years Ended December 31,
﻿ |  | 2017 |  | 2016 |  | 2015
﻿Revenues |  | $ | 4,683 |  | $ | 4,113 |  | $ | 5,631
﻿Production costs and taxes |  |  | (3,444) |  |  | (3,064) |  |  | (3,731)
﻿Depreciation, depletion and amortization |  |  | (796) |  |  | (1,009) |  |  | (2,538)
﻿Impairment |  |  | — |  |  | (2,805) |  |  | (14,526)
﻿Income (loss) from oil and gas producing activities |  | $ | 443 |  | $ | (2,765) |  | $ | (15,164)
﻿
Schedule Of Net Proved Oil And Gas Reserves And The Changes In Net Proved Oil And Gas Reserves |
﻿ |  |  |  |  |  |
﻿ |  |  |  |  |  |
﻿ |  | Oil (MBbl) |  | Gas (MMcf) |  | MBOE
﻿Proved reserves at December 31, 2014 |  | 1,797 |  | — |  | 1,797
﻿Revisions of previous estimates |  | (790) |  | — |  | (790)
﻿Improved recovery |  | — |  | — |  | —
﻿Purchase of reserves in place |  | — |  | — |  | —
﻿Extensions and discoveries |  | 1 |  | — |  | 1
﻿Production |  | (131) |  | — |  | (131)
﻿Sales of reserves in place |  | — |  | — |  | —
﻿Proved reserves at December 31, 2015 |  | 877 |  | — |  | 877
﻿Revisions of previous estimates |  | (36) |  | — |  | (36)
﻿Improved recovery |  | — |  | — |  | —
﻿Purchase of reserves in place |  | — |  | — |  | —
﻿Extensions and discoveries |  | 3 |  | — |  | 3
﻿Production |  | (108) |  | — |  | (108)
﻿Sales of reserves in place |  | (6) |  | — |  | (6)
﻿Proved reserves at December 31, 2016 |  | 730 |  | — |  | 730
﻿Revisions of previous estimates |  | 195 |  | — |  | 195
﻿Improved recovery |  | — |  | — |  | —
﻿Purchase of reserves in place |  | — |  | — |  | —
﻿Extensions and discoveries |  | 47 |  | — |  | 47
﻿Production |  | (102) |  | — |  | (102)
﻿Sales of reserves in place |  | — |  | — |  | —
﻿Proved reserves at December 31, 2017 |  | 870 |  | — |  | 870
﻿ |  |  |  |  |  |
﻿Proved developed reserves at: |  |  |  |  |  |
﻿December 31, 2014 |  | 1,438 |  | — |  | 1,438
﻿December 31, 2015 |  | 877 |  | — |  | 877
﻿December 31, 2016 |  | 730 |  | — |  | 730
﻿December 31, 2017 |  | 832 |  | — |  | 832
﻿ |  |  |  |  |  |
﻿Proved undeveloped reserves at: |  |  |  |  |  |
﻿December 31, 2014 |  | 359 |  | — |  | 359
﻿December 31, 2015 |  | — |  | — |  | —
﻿December 31, 2016 |  | — |  | — |  | —
﻿December 31, 2017 |  | 38 |  | — |  | 38
﻿
Schedule Of Reserve Value By Category And The Respective Present Values, Before Income Taxes, Discounted At 10% As A Percentage Of Total Proved Reserves |
﻿ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
﻿ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
﻿ |  | Year Ended 12/31/2017 |  | Year Ended 12/31/2016 |  | Year Ended 12/31/2015
﻿ |  | Oil |  | Gas |  | Total |  | Oil |  | Gas |  | Total |  | Oil |  | Gas |  | Total
﻿Total proved reserves year-end reserve report |  | $ | 8,170 |  |  | — |  | $ | 8,170 |  | $ | 5,815 |  |  | — |  | $ | 5,815 |  | $ | 8,287 |  |  | — |  | $ | 8,287
﻿Proved developed producing reserves (PDP) |  | $ | 7,065 |  |  | — |  | $ | 7,065 |  | $ | 5,397 |  |  | — |  | $ | 5,397 |  | $ | 7,686 |  |  | — |  | $ | 7,686
﻿% of PDP reserves to total proved reserves |  |  | 87% |  |  | — |  |  | 87% |  |  | 93% |  |  | — |  |  | 93% |  |  | 93% |  |  | — |  |  | 93%
﻿Proved developed non- producing reserves |  | $ | 1,082 |  |  | — |  | $ | 1,082 |  | $ | 418 |  |  | — |  | $ | 418 |  | $ | 601 |  |  | — |  | $ | 601
﻿% of PDNP reserves to total proved reserves |  |  | 13% |  |  | — |  |  | 13% |  |  | 7% |  |  | — |  |  | 7% |  |  | 7% |  |  | — |  |  | 7%
﻿Proved undeveloped reserves (PUD) |  | $ | 23 |  |  | — |  | $ | 23 |  | $ | — |  |  | — |  | $ | — |  | $ | — |  |  | — |  | $ | —
﻿% of PUD reserves to total proved reserves |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | —
﻿
Schedule Of Standardized Measure Of Discounted Futures Net Cash Flows From Proved Oil And Gas Reserves |
﻿ |  |  |  |  |  |  |  |  |
﻿ |  |  |  |  |  |  |  |  |
﻿ |  | Years Ended December 31,
﻿ |  | 2017 |  | 2016 |  | 2015
﻿Future cash inflows |  | $ | 39,889 |  | $ | 27,253 |  | $ | 38,566
﻿Future production costs and taxes |  |  | (23,343) |  |  | (16,270) |  |  | (23,500)
﻿Future development costs |  |  | (1,586) |  |  | (553) |  |  | (951)
﻿Future income tax expenses |  |  | — |  |  | — |  |  | —
﻿Future net cash flows |  |  | 14,960 |  |  | 10,430 |  |  | 14,115
﻿ |  |  |  |  |  |  |  |  |
﻿Discount at 10% for timing of cash flows |  |  | (6,790) |  |  | (4,615) |  |  | (5,828)
﻿Standardized measure of discounted future net cash flows |  | $ | 8,170 |  | $ | 5,815 |  | $ | 8,287
﻿
Schedule Of Changes In The Standardized Measure Of Discounted Future Net Cash Flows From Proved Oil And Gas Reserves |
﻿ |  |  |  |  |  |  |  |  |
﻿ |  |  |  |  |  |  |  |  |
﻿ |  | Years Ended December 31,
﻿ |  | 2017 |  | 2016 |  | 2015
﻿Balance, beginning of year |  | $ | 5,815 |  | $ | 8,287 |  | $ | 34,531
﻿Sales, net of production costs and taxes |  |  | (1,239) |  |  | (2,037) |  |  | (1,901)
﻿Discoveries and extensions, net of costs |  |  | 123 |  |  | 35 |  |  | 5
﻿Purchase of reserves in place |  |  | — |  |  | — |  |  | —
﻿Sale of reserves in place |  |  | — |  |  | (10) |  |  | —
﻿Net changes in prices and production costs |  |  | 1,780 |  |  | (863) |  |  | (16,009)
﻿Revisions of quantity estimates |  |  | 1,611 |  |  | (412) |  |  | (22,431)
﻿Previously estimated development cost incurred during the year |  |  | — |  |  | — |  |  | —
﻿Changes in future development costs |  |  | (228) |  |  | 196 |  |  | 4,890
﻿Changes in timing and other |  |  | (164) |  |  | (20) |  |  | (56)
﻿Accretion of discount |  |  | 472 |  |  | 639 |  |  | 3,373
﻿Net change in income taxes |  |  | — |  |  | — |  |  | 5,885
﻿Balance, end of year |  | $ | 8,170 |  | $ | 5,815 |  | $ | 8,287
﻿

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- Definition Tabular disclosure of aggregate capitalized costs relating to an enterprise's oil and gas producing activities and the aggregate related accumulated depreciation, depletion, amortization, and valuation allowances. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61901-109447 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 55 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=34713648&loc=d3e63019-109448 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61929-109447 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61926-109447 + Details
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- Definition Tabular disclosure of the net quantities of an enterprise's interests in proved developed and undeveloped reserves of (a) crude oil (including condensate and natural gas liquids), (b) natural gas (including coal bed methane), (c) synthetic oil, (d) synthetic gas, and (e) other nonrenewable natural resources that are intended to be upgraded during the period as of the beginning of the period, changes in quantities during the period, and as of the end of the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61858-109447 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61884-109447 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61797-109447 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61869-109447 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61872-109447 + Details
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