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Hedging Activities (Tables) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2013 | Dec. 31, 2012
General Discussion of Derivative Instruments and Hedging Activities [Abstract] |  |
Schedule Of Derivative Instruments | At March 31, 2013, the Company had the following fixed price swaps in place:
| Daily Volume (Bbls/day) |  | Weighted Average Price
April - June 2013 | 5,000 |  |  | $ | 101.96 |
July - December 2013 | 5,000 |  |  | $ | 99.86 |
| At December 31, 2012, the Company had the following fixed price swaps in place:
| Daily Volume (Bbls/day) |  | Weighted Average Price
January - December 2013 | 5,000 |  |  | $ | 100.90 |
Schedule Of Derivative Instruments In Statement Of Financial Position | At March 31, 2013 the fair value of derivative assets related to the fixed price swaps was as follows:
| (In thousands)
Short-term derivative instruments - asset | $ | 343 |
Short-term derivative instruments - liability | $ | 9,689 |
| At December 31, 2012 the fair value of derivative assets related to the fixed price swaps was as follows:
Short-term derivative instruments - asset | $ | 664,000 |
Short-term derivative instruments - liability | $ | 10,442,000 |
At December 31, 2011, the fair value of derivative assets related to the fixed price swaps was as follows:
Short-term derivative instruments - asset | $ | 1,601,000 |
Schedule Of Cash Flow Hedges | Amounts reclassified out of accumulated other comprehensive income (loss) into earnings as a component of oil and condensate sales for the three months ended March 31, 2013 and 2012 are presented below.
| Three Months Ended March 31,
| 2013 |  | 2012
| (In thousands)
(Reduction) addition to oil and condensate sales | $ | (2,957 | ) |  | $ | 100 |
| Amounts reclassified out of accumulated other comprehensive income into earnings as a component of oil and condensate sales for the years ended December 31, 2012 and 2011 are presented below.
| Year ended December 31,
| 2012 |  | 2011
(Reduction) addition to oil and condensate sales | $ | (1,517,000 | ) |  | $ | (4,720,000 | )
Schedule Of Cumulative Hedging Activities Included In Accumulated Other Comprehensive Income |  | The following table presents the balances of the Company’s cumulative hedging activities included in other comprehensive income.
December 31, 2009 | $ | (18,736,000 | )
December 31, 2010 | $ | (4,720,000 | )
December 31, 2011 | $ | 1,576,000 |
December 31, 2012 | $ | (9,660,000 | )

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- Definition Tabular disclosure of the effective portion of gains and losses on derivative instruments (and nonderivative instruments) designated and qualifying in cash flow hedges recorded in accumulated other comprehensive income (loss) during the term of the hedging relationship and reclassified into earnings during the current period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959 + Details
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- Definition Tabular disclosure of the location and fair value amounts of derivative instruments (and nonderivative instruments that are designated and qualify as hedging instruments) reported in the statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 205G -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44C -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition Tabular disclosure of pertinent information about a derivative or group of derivatives on a disaggregated basis, such as for individual instruments, or small groups of similar instruments. May include a combination of the type of instrument, risks being hedged, notional amount, hedge designation, related hedged item, inception date, maturity date, or other relevant item. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(n)(2)) -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41678-113959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41620-113959 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579240-113959 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41641-113959 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41638-113959 Reference 10: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959 Reference 11: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 25 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986 + Details
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