Percentage of oil reserves.

No definition available.

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- Definition

Percentage of proved developed reserves.

+ References

No definition available.

+ Details

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- Definition

Energy volume of an entity's interests in proved developed reserves of crude oil (including condensate and natural gas liquids), natural gas, synthetic oil and gas, or other nonrenewable natural resource that is intended to be upgraded into synthetic oil and gas.

+ References

No definition available.

+ Details

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- Definition

Working interest by acquiree prior to acquisition.

+ References

No definition available.

+ Details

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- Definition

Working Interest by acquirer prior to acquistion.

+ References

No definition available.

+ Details

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- Definition

Amount of cash paid to acquire the entity.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph f(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 141

-Paragraph 51

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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- Definition

Percentage of voting equity interests acquired in the business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph c

-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.

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- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

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-Topic 835

-SubTopic 30

-Section 55

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

-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.

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- 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

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-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.

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-Topic 210

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-Subparagraph (SX 210.5-02.19(b),22(b))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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Organization and Summary of Significant Accounting Policies (Narrative) (Details) (USD $)	0 Months Ended		12 Months Ended		0 Months Ended			0 Months Ended
	Mar. 31, 2012 South Timbalier Acquisition [Member] MMBoe	May 15, 2012 South Timbalier Acquisition [Member]	Dec. 31, 2012 Hilcorp Acquisition [Member] MMBoe	Oct. 31, 2012 Hilcorp Acquisition [Member]	Dec. 31, 2010 ASOP Acquisition [Member] MMBoe	Feb. 14, 2012 ASOP Acquisition [Member]	Feb. 14, 2011 ASOP Acquisition [Member]	Nov. 01, 2011 Main Pass Acquisition [Member] MMBoe	Nov. 17, 2012 Main Pass Acquisition [Member]	Dec. 17, 2011 Main Pass Acquisition [Member]	Dec. 31, 2012 2012 Notes [Member]	Oct. 25, 2012 2012 Notes [Member]	Oct. 31, 2012 2012 Notes [Member] Hilcorp Acquisition [Member]	Dec. 31, 2012 2011 Notes [Member]	Feb. 14, 2011 2011 Notes [Member]	Oct. 31, 2012 Senior Credit Facility [Member]	Oct. 30, 2012 Senior Credit Facility [Member]	Feb. 14, 2011 Senior Credit Facility [Member]
Business Acquisition [Line Items]
Percent of member interests acquired				100.00%
Acquired certain interests in producing oil and natural gas assets		$ 32,400,000		$ 550,000,000		$ 200,700,000	$ 200,700,000		$ 38,600,000	$ 38,600,000					$ 200,700,000
Senior Notes, face amount						210,000,000					300.0	300.0	300,000,000	210,000,000	210.0
Senior Notes, stated percentage											8.25%			8.25%
Senior secured credit facility																750,000,000	250,000,000	250,000,000
Proved developed reserves, Mmboe	1.0		37.2		8.1			1.3
Percentage of Oil Reserves	51.00%		49.00%		84.00%			96.00%
Percentage of Proved Developed Reserves	84.00%		58.00%		76.00%
Working Interest by Acquirer Prior to Acquistion		60.00%
Working Interest by Acquiree Prior To Acquisition		40.00%
Line of Credit Facility, Maximum Borrowing Capacity																$ 750,000,000	$ 250,000,000	$ 250,000,000