Business and Organization (Details)	12 Months Ended
	Dec. 31, 2011 Subsidiaries
Business and Organization
Minimum annual REIT taxable income distributable to stockholders (as a percent)	90.00%
Number of wholly owned subsidiaries	3
Percentage of ownership in Joint Ventures	75.00%
Investments with collateral in the hospitality sector (as a percent)	39.90%
Investments with collateral in the retail sector (as a percent)	21.00%
Investments with collateral in the office property sector (as a percent)	20.10%