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Income Taxes (Narrative) (Details) (USD $) | 12 Months Ended
--- | ---
Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Operating Loss Carryforwards [Line Items] |  |  |
Altermative minimum tax credits | $ 1,643,000 | $ 1,000,000 | $ 693,000
Foreign tax credit carryforwards | 2,074,000 | 0 | 0
Valuation allowance for deferred tax assets | 4,629,000 | 12,347,000 | 54,434,000
Change in deferred tax asset valuation | (9,792,000) | (42,087,000) | (18,818,000)
Deferred tax expense | 25,633,000 |  |
Current state and local tax expense (benefit) | 84,000 | 0 | 40,000
Federal [Member] |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Net operating loss carryforward | 4,323,000 |  |
Oklahoma and Louisiana [Member] |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Net operating loss carryforward | 84,031,000 |  |
Diamondback [Member] |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Taxable gain on contribution | $ (61,900,000) |  |

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- Definition The component of income tax expense for the period representing amounts paid or payable (or refundable) as determined by applying the provisions of enacted state and local tax law to relevant amounts of taxable Income or Loss from continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I.7) -URI http://asc.fasb.org/extlink&oid=6889476&loc=d3e330036-122817 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Current Tax Expense (or Benefit) -URI http://asc.fasb.org/extlink&oid=6509736 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319 Reference 4: 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.(h)) -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 45 -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 6: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Article 4 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 6 -Section I -Subsection 7 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 289 -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 The component of income tax expense for the period representing the increase (decrease) in the entity's deferred tax assets and liabilities pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 45 -Subparagraph b -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 Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 -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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I.7) -URI http://asc.fasb.org/extlink&oid=6889476&loc=d3e330036-122817 Reference 5: 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.(h)) -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Article 4 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 6 -Section I -Subsection 7 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 289 -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 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Deferred Tax Expense (or Benefit) -URI http://asc.fasb.org/extlink&oid=6510177 Reference 10: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319 + Details
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