Investments in Unconsolidated Joint Ventures (Details 4) (Gramercy Capital Corp., USD $) Share data in Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Jun. 30, 2012 sqft
Related Party Transactions
Shares held of Gramercy's common stock	0.7
Percentage of Gramercy's common stock owned	1.30%
Total investment in Gramercy based on market value of common stock	$ 3,900,000
First Gramercy lease
Related Party Transactions
Space leased (in square feet)	7,300
Annual lease rent for year one	249,000
Annual lease rent for year ten	315,000
Second Gramercy lease
Related Party Transactions
Space leased (in square feet)	900
Annual lease rent for year one	35,300
Annual lease rent for year six	42,800
New Gramercy lease
Related Party Transactions
Space leased (in square feet)		8,100
Annual lease rent for year one	345,000
Annual lease rent for year three	357,000
Third Gramercy lease
Related Party Transactions
Space leased (in square feet)	1,400
Annual lease rent for year one	67,300
Annual lease rent for year six	$ 80,500

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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+ Details

- Definition

Balance held at close of period in number of shares.

+ References+ Details