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Significant Accounting Policies (Details 7) (USD $)	12 Months Ended
	Dec. 31, 2011 bank	Dec. 31, 2011 Cash balances with financial institutions Credit concentration risk Minimum	Dec. 31, 2010 Annualized rental revenues Single tenant rental revenues
Concentration of Credit Risks
Number of banks in which the entity maintains cash balances	2
Uninsured deposit threshold amount		$ 250,000
Insurance limit provided by Federal Deposit Insurance Corporation	$ 250,000
Percentage of annualized rental revenues required for qualification as major tenant			10.00%

X

- Definition

For an entity that discloses a concentration risk in relation to a quantitative amount, which serves as the "benchmark" in the equation, this concept represents the insurance limit provided by the Federal Deposit Insurance Corporation, for which deposits at a financial institution in excess of this amount are uninsured.

+ References

No definition available.

+ Details

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X

- Definition

Represents the number of banks in which the entity maintains cash balances.

+ References

No definition available.

+ Details

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X

- Definition

The amount of cash deposited in financial institutions as of the balance sheet date that is insured by the Federal Deposit Insurance Corporation.

+ References

No definition available.

+ Details

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- Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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

-Publisher FASB

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