Leasehold Acres Consideration to Acquire Unproved Property

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- Definition

Net acres acquired

+ References

No definition available.

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- Definition

Working Capital Acquired

+ References

No definition available.

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- Definition

Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

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.

+ References

No definition available.

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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=35744172&loc=d3e2207-128464

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- Definition

Oil and gas properties net of accumulated depreciation, depletion, amortization, impairment, and abandonment, carried under the successful effort method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=51678428&loc=d3e61901-109447

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-Section S99
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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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- Definition

The cash outflow to purchase long lived physical asset for use in the normal oil and gas operations and to purchase mineral interests in oil and gas properties not intended for resale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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- Definition

Oil and Gas properties with proved reserves under the successful effort method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 360
-Glossary Proved Properties
-URI http://asc.fasb.org/extlink&oid=6522428

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- Definition

Oil and Gas properties with unproved reserves under the successful effort method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=51678428&loc=d3e61926-109447

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-Glossary Unproved Properties
-URI http://asc.fasb.org/extlink&oid=6527831

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Acquisitions (Details) a in Thousands, $ in Thousands			12 Months Ended
Acquisitions (Details) a in Thousands, $ in Thousands	Oct. 15, 2014 USD ($)	Sep. 24, 2014 USD ($) a	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($) a	Dec. 31, 2013 USD ($)
Business Acquisition [Line Items]
Proved Oil and Gas Property, Successful Effort Method			$ 7,606,405	$ 7,348,436
Unproved Oil and Gas Property, Successful Effort Method			284,538	532,498
Asset Retirement Obligations, Noncurrent			(137,525)	(120,867)
Payments to Acquire Oil and Gas Property and Equipment			$ 7,984	544,553	$ 61,603
Gooseneck Prospect Acquisition 2014 [Member]
Business Acquisition [Line Items]
Net acres acquired \| a		61
Payments to Acquire Businesses, Gross		$ 321,807
Proved Oil and Gas Property, Successful Effort Method		203,467
Unproved Oil and Gas Property, Successful Effort Method		126,588
Oil and Gas Property, Successful Effort Method, Net		330,055
Working Capital Acquired		(6,135)
Asset Retirement Obligations, Noncurrent		(2,113)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net		$ 321,807
Gooseneck Second Prospect Acquisition 2014 [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	$ 84,836
Proved Oil and Gas Property, Successful Effort Method	54,612
Unproved Oil and Gas Property, Successful Effort Method	29,610
Oil and Gas Property, Successful Effort Method, Net	84,222
Working Capital Acquired	2,232
Asset Retirement Obligations, Noncurrent	(1,618)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	$ 84,836
Rocky Mountain Acquisition 2014 [Member]
Business Acquisition [Line Items]
Payments to Acquire Oil and Gas Property and Equipment				$ 135,500
Leasehold Acres Consideration to Acquire Unproved Property \| a				7