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Represents the amount recognized for uncertain tax positions as of the balance sheet date.

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No definition available.

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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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- Definition

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

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No definition available.

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- Definition

Subsidiary treated as a taxable real estate investment trust.

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No definition available.

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- Definition

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

-Publisher FASB

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-Name Regulation S-X (SX)

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-Article 7

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Amount of non-cash amortization of intangible asset (liability) for above and below market leases.

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No definition available.

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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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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The component of income tax expense for the period representing amounts paid or payable (or refundable) as determined by applying the provisions of enacted federal tax law to the domestic taxable Income or Loss from continuing operations.

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Summary of Significant Accounting Policies (Details 3) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 item	Jun. 30, 2012	Dec. 31, 2012
Revenue Recognition
Increase to rental revenue	$ 200,000	$ 400,000	$ 400,000	$ 800,000
Allowance for doubtful accounts (in dollars)	347,000		347,000		625,000
Asset Retirement and Environmental Remediation Obligations
Asset retirement and environmental remediation obligations	2,500,000		2,500,000		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		$ 0
Number of subsidiaries treated as a taxable REIT			2