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PROPERTY AND EQUIPMENT (Summary of Non-producing Properties Excluded from Amortization by Area) (Details) - USD ($) $ in Thousands | Sep. 30, 2018 | Dec. 31, 2017
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Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items] |  |
Total non-producing properties not subject to amortization | $ 2,925,145 | $ 2,912,974
Utica |  |
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items] |  |
Total non-producing properties not subject to amortization | 1,522,633 |
MidContinent |  |
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items] |  |
Total non-producing properties not subject to amortization | 1,401,392 |
Niobrara |  |
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items] |  |
Total non-producing properties not subject to amortization | 449 |
Southern Louisiana |  |
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items] |  |
Total non-producing properties not subject to amortization | 571 |
Bakken |  |
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items] |  |
Total non-producing properties not subject to amortization | $ 100 |

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- Definition The sum of the capitalized costs incurred, as of the balance sheet date, of unproved properties excluded from amortization including acquisition costs, exploration costs, development costs, and production costs. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10.(c)(7)(ii)) -URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862 + Details
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