Concentration Risks	12 Months Ended
Dec. 31, 2011
Concentration Risks	18. Concentration Risks The Company has historically relied on Wells Fargo Bank, N. A. (as successor to Wachovia Bank, N. A.) to provide a significant portion of its cash for financing its portfolio investments, including through short-term borrowing facilities to facilitate the Company’s portfolio investment and mortgage financings on its owned real properties. Deterioration in the financial condition of Wells Fargo Bank, N. A. could have a negative impact on the Company’s business, operating results and financial condition. As of December 31, 2011, Wells Fargo Bank, N. A. carried a senior unsecured credit rating of AA- from Standard & Poor’s. During 2011, approximately 12.8% of the Company’s total revenues were derived from one tenant (the United States Government).

Concentration Risks

12 Months Ended

Dec. 31, 2011

18. Concentration Risks

The Company has historically relied on Wells Fargo Bank, N. A. (as successor to Wachovia Bank, N. A.) to provide a significant portion of its cash for financing its portfolio investments, including through short-term borrowing facilities to facilitate the Company’s portfolio investment and mortgage financings on its owned real properties. Deterioration in the financial condition of Wells Fargo Bank, N. A. could have a negative impact on the Company’s business, operating results and financial condition. As of December 31, 2011, Wells Fargo Bank, N. A. carried a senior unsecured credit rating of AA- from Standard & Poor’s.

During 2011, approximately 12.8% of the Company’s total revenues were derived from one tenant (the United States Government).

- Definition

The entire disclosure for any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. This disclosure informs financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date.

+ References

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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+ Details