Commitments And Contingencies [Line Items]

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- Definition

Future Obligations Under Cost Sharing Agreements

+ References

No definition available.

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- Definition

Future Obligations Under Purchase Agreements

+ References

No definition available.

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- Definition

Future obligations under supply agreements

+ References

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- Definition

The maximum duration period applicable to the existing commitments.

+ References

No definition available.

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- Definition

Oil and Gas, Rig Termination Expense

+ References

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

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-Name Accounting Standards Codification

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-SubTopic 20

-Section 50

-Paragraph 9

-Subparagraph (b)

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- Definition

Number of defendants named in a legal action.

+ References

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- Definition

Total amount of product committed to be supplied under existing contracts or agreements.

+ References

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

-Publisher SEC

-Name Regulation S-K (SK)

-Number 229

-Section 1207

-Paragraph (a)

-Subparagraph (2)

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- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

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Commitments and Contingencies - Additional Information (Detail) $ in Thousands		3 Months Ended		6 Months Ended
	Jul. 06, 2013 defendant	Jun. 30, 2015 USD ($) MBbls MMcf	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) MBbls MMcf	Jun. 30, 2014 USD ($)
Commitments And Contingencies [Line Items]
Total rental commitments under leases		$ 30,700		$ 30,700
Rig termination		2,815	$ 0	3,895	$ 0
Future obligations under purchase agreements				38,900
Future obligations under cost sharing agreements				4,500
Number of named defendants (over) \| defendant	50
Long Term Commitments [Member]
Commitments And Contingencies [Line Items]
Future obligations under supply agreements				185,600
Drilling contracts [Member]
Commitments And Contingencies [Line Items]
Rig termination		2,800
Payments upon early contract termination		$ 8,500		$ 8,500
Williston Basin Project [Member] \| Long Term Commitments [Member]
Commitments And Contingencies [Line Items]
Maximum commitment term				10 years
Williston Basin Project [Member] \| Long Term Commitments [Member] \| Crude oil [Member]
Commitments And Contingencies [Line Items]
Minimum quantity of delivery \| MBbls		30,200		30,200
Williston Basin Project [Member] \| Long Term Commitments [Member] \| Natural Gas [Member]
Commitments And Contingencies [Line Items]
Minimum quantity of delivery \| MMcf		5,300		5,300