Derivative Financial Instruments (Details) $ in Thousands	3 Months Ended
Mar. 31, 2017 USD ($) MMBTU $ / MMBTU	Mar. 31, 2016 USD ($)
Commodity Derivatives [Abstract]
Realized (loss) gain on commodity derivatives - natural gas	$ 0	$ 0
Unrealized Gain (Loss) on Derivatives	(13,218)	0
Gain loss on commodity derivatives	$ (13,218)	$ 0
Natual Gas \| Nymex Henry Hub
Derivative Financial Instruments (Details)
DerivativeSwapType	Fixed price swap
Volume per day \| MMBTU	555,374
Average Price \| $ / MMBTU	3.17
Fair Value	$ (13,218)
Derivative remaining maturity date	Apr - Oct 2017

Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- References

No definition available.

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- Definition

Period remaining until the derivative contract matures.

+ References

No definition available.

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- Definition

The realized gain (loss) on commodity derivatives relating to actual amounts received or paid under the respective contracts and the unrealized gain or loss on commodity derivative contracts representing the change in the fair market value of derivative instruments that have not actually settled.

+ References

No definition available.

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- Definition

Actual amounts received or paid related to natural gas derivative instruments, including options, swaps, futures, and forward contracts, which were included in earnings in the period.

+ References

No definition available.

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- References

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- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (a),(c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624163-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226000-175313

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=64830801&loc=SL51823488-111719

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- Definition

Indicates whether the entity pays a variable or fixed price on a price risk swap.

+ References

No definition available.

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- Definition

Average fixed price related to the group of price risk swap derivatives.

+ References

No definition available.

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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