Commitments and Contingencies Commitments and Contingencies (Details) (CONSOL Carried Cost Obligation [Member], USD $)	3 Months Ended
Mar. 31, 2015
CONSOL Carried Cost Obligation [Member]
Other Commitments [Line Items]
Equity method investment, ownership percentage	50.00%
Maximum amount to be paid each calendar year for funding of future drilling and completion costs	$ 400,000,000
Funding of joint venture's future drilling and completion costs	1,600,000,000
Natural gas price agreed upon benchmark, average	$ 4.00

Amount agreed upon to provide funding of the entity's joint venture future drilling and completion costs.

No definition available.

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- Definition

The maximum amount of funding to be provided by the entity for future drilling and completion cost each calendar year.

+ References

No definition available.

+ Details

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- Definition

Average natural gas price agreed upon benchmark for funding of future drilling and completion costs (in MMBtu's). If the average price of gas drops below benchmark for 3 consecutive months, capital carry will to be suspended until the average price of gas rises above the benchmark for a 3 consecutive month period.

+ References

No definition available.

+ Details

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

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- Details

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