Summary of Significant Accounting Policies (Details 4) (USD $)	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012
Revenue Recognition
Allowance for doubtful accounts (in dollars)	$ 159,000	$ 625,000
Asset Retirement and Environmental Remediation Obligations
Asset retirement and environmental remediation obligations	2,200,000	2,600,000
Income taxes
Minimum percentage of distribution of taxable income to qualify as REIT	90.00%
Percentage of distribution of taxable income as per company policy	100.00%
Provision for federal income taxes	0
Liabilities for uncertain positions	$ 0

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Represents the minimum percentage of distribution of taxable income by the entity to qualify as a REIT.

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No definition available.

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Represents the percentage of distribution of taxable income as per policy of the entity.

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The valuation allowance as of the balance sheet date to reduce the gross amount of receivables to estimated net realizable value, which would be presented in parentheses on the face of the balance sheet.

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

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The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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