Supplemental Gas Data Average Unit Prices (Details) (USD $)	12 Months Ended
Dec. 31, 2014 MMcf	Dec. 31, 2013 MMcf	Dec. 31, 2012 MMcf
Average Sales Price and Production Costs Per Unit of Production [Line Items]
Oil and Gas Delivery Commitments and Contracts, Remaining Contractual Volume	153.5
Proved Developed and Undeveloped Reserves, Production	235,714,000	172,380,000	156,325,000
Natural Gas, Per Thousand Cubic Feet [Member]
Average Sales Price and Production Costs Per Unit of Production [Line Items]
Average Gas Sales Price before effects of financial settlements	4.26	3.85	3.00
Average effects of financial settlements (per thousand cubic feet)	0.11	0.45	1.22
Average gas sales price including effects of financial settlements (per thousand cubic feet)	4.37	4.30	4.22
Average lifting costs, excluding ad valorem and severance taxes (per thousand cubic feet)	.5	.56	.58

Average effects of financial settlements (per thousand cubic feet)

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Average Gas Sales Price before effects of financial settlements

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Average gas sales price including effects of financial settlements (per thousand cubic feet)

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- Definition

Summary of significant aspects of production costs of the energy source on a per unit basis. This information is presented in different formats, including certain specific costs, summarized costs or costs in total.

+ References

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-Publisher SEC

-Name Industry Guide

-Number 2

-Paragraph 3

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

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-Publisher SEC

-Name Industry Guide

-Number 2

-Paragraph 8

-Subparagraph A

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Production of proved reserves.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section 50

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