Consolidated Statements of Operations (Parenthetical) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
OIL AND GAS SALES, net gain or (loss) from ineffectiveness of derivatives	$ (2,072)	$ (116)	$ (1,349)	$ (1,373)

The portion of a hedge deemed to be ineffective that is reflected in current period results of operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

Name:	us-gaap_DerivativeNetHedgeIneffectivenessGainLoss
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration