v2.4.0.6

Derivative Financial Instruments (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012 Crude oil	Sep. 30, 2011 Crude oil	Sep. 30, 2012 Crude oil	Sep. 30, 2011 Crude oil	Sep. 30, 2012 Natural gas	Sep. 30, 2011 Natural gas	Sep. 30, 2012 Natural gas	Sep. 30, 2011 Natural gas	Sep. 30, 2012 Natural gas liquids ("NGLs")	Sep. 30, 2011 Natural gas liquids ("NGLs")	Sep. 30, 2012 Natural gas liquids ("NGLs")	Sep. 30, 2011 Natural gas liquids ("NGLs")	Sep. 30, 2012 Convertible Debt [Member]	Dec. 31, 2011 Convertible Debt [Member]
Unrealized and realized gain and loss from derivative cash settlements and changes in fair value of derivative contracts
Cash settlement (gain) and loss	$ (10,921)	$ 3,755	$ (32,803)	$ 24,148	$ 2,472	$ 1,058	$ 13,142	$ 18,421	$ (9,031)	$ (1,434)	$ (40,495)	$ (3,751)	$ (4,362)	$ 4,131	$ (5,450)	$ 9,478
Unrealized (gain) loss on changes in fair value	(66,777)	132,180	7,237	108,020	(30,667)	106,780	32,616	90,629	(28,231)	19,083	(40,464)	21,504	(7,879)	6,317	15,085	(4,113)
Unrealized and Realized Derivative (Gain) Loss	55,856	(128,425)	(40,040)	(83,872)
Amount of (gain) loss reclassified from AOCL to realized hedge gain (loss)	(315)	4,271	(1,465)	9,149
Realized hedge gain (loss)	$ 501	$ (6,843)	$ 2,338	$ (14,548)
Interest rate on notes (as a percent)																	3.50%	3.50%

X

- Definition

Amount of realized gain (loss) recognized in earnings in the period from the settlement of commodity derivative instruments not designated as cash flow hedges.

+ References

No definition available.

+ Details

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X

- Definition

The change in the market value of derivative instruments and realized derivatives settled within the period that were not previously designated as cash flow hedges.

+ References

No definition available.

+ Details

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X

- Definition

Interest rate stated in the contractual debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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X

- Details

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X

- Definition

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5618551-113959

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X

- Definition

Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of price risk derivatives not designated as hedging instruments.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44

-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 4C

-Subparagraph (e)

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

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X

- Definition

The amount of net gains or losses on price risk cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income.

+ References

No definition available.

+ Details

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