Commitments And Contingencies [Line Items]

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- Definition

Future Obligations Under Purchase Agreements

+ References

No definition available.

+ Details

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- Definition

Future obligations under supply agreements

+ References

No definition available.

+ Details

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- Definition

The maximum duration period applicable to the existing commitments.

+ References

No definition available.

+ Details

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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)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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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)
-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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

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- Details

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- Details

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Commitments and Contingencies - Additional Information (Details) - 3 months ended Mar. 31, 2016 $ in Millions	USD ($)	MBbls	MMcf
Commitments And Contingencies [Line Items]
Total rental commitments under leases	$ 24.6
Future obligations under purchase agreements	42.4
Long Term Commitments [Member]
Commitments And Contingencies [Line Items]
Future obligations under supply agreements	$ 446.2
Williston Basin Project [Member] \| Long Term Commitments [Member]
Commitments And Contingencies [Line Items]
Maximum commitment term (less than)	10 years
Williston Basin Project [Member] \| Crude oil [Member] \| Long Term Commitments [Member]
Commitments And Contingencies [Line Items]
Minimum quantity of delivery (in MBbl of crude oil, MBbl of natural gas liquids, and MMcf of natural gas) \| MBbls		32,500
Williston Basin Project [Member] \| Natural Gas [Member] \| Long Term Commitments [Member]
Commitments And Contingencies [Line Items]
Minimum quantity of delivery (in MBbl of crude oil, MBbl of natural gas liquids, and MMcf of natural gas)		23,000	221,800
Drilling contracts [Member]
Commitments And Contingencies [Line Items]
Payments upon early contract termination	$ 1.8