AMORTIZING INTANGIBLE ASSETS AND UNFAVORABLE GAS GATHERING CONTRACT - Estimated Aggregate Annual Amortization Expected to be Recognized (Details) $ in Thousands	Dec. 31, 2016 USD ($)
Intangible assets
2017	$ 41,854
2018	41,323
2019	41,154
2020	43,403
2021	41,630
Unfavorable gas gathering contract
2017	2,158
2018	1,888
2019	0
2020	0
2021	$ 0

Finite lived noncurrent liability future amortization income.

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- Definition

Finite lived unfavorable contract amortization income, next fiscal year.

+ References

No definition available.

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- Definition

Amount of amortization income expected to be recognized during the fifth fiscal year following the latest fiscal year for unfavorable contract with a finite life.

+ References

No definition available.

+ Details

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- Definition

Amount of amortization income expected to be recognized during the fourth fiscal year following the latest fiscal year for unfavorable contract with a finite life.

+ References

No definition available.

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- Definition

Amount of amortization income expected to be recognized during the third fiscal year following the latest fiscal year for unfavorable contract with a finite life.

+ References

No definition available.

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- Definition

Amount of amortization income expected to be recognized during the second fiscal year following the latest fiscal year for unfavorable contract with a finite life.

+ References

No definition available.

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- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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