TRANSACTIONS WITH AFFILIATES AND OTHER RELATED PARTIES Transactions with Affiliates and Other Related Parties (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
PDCM
Related Party Transaction [Line Items]
Related party transactions included in cost of natural gas marketing	$ 23,200	$ 18,100
Well operating and administrative services on behalf of PDCM	5,700	14,500
Due from PDCM	$ 0
Affiliated Partnerships
Related Party Transaction [Line Items]
Related party transactions included in cost of natural gas marketing		$ 1,300

Amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership, due within 1 year (or 1 business cycle).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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