Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Operating (including $355,241 and $282,303 of consolidated variable interest entities, respectively)	$ 355,241	$ 282,303
Less accumulated depreciation and amortization (including $30,099 and $26,618 of consolidated variable interest entities, respectively)	30,099	26,618
Debt issuance costs, net of accumulated amortization of $11,796 and $11,441, respectively	11,796	11,441
Mortgages payable (including $179,303 and $187,632 of consolidated variable interest entities, respectively)	$ 179,303	$ 187,632
Preferred shares, authorized	15,000,000	15,000,000
Preferred shares, par	$ 0.01	$ 0.01
Preferred Shares, percentage	5.417%	5.417%
Preferred Shares, 5.417% Series 1 Cumulative Convertible liquidation preference	$ 25	$ 25
Preferred shares, shares issued	399,896	399,896
Preferred shares, shares outstanding	399,896	399,896
Common shares of beneficial interest, par	$ 0.01	$ 0.01
Common shares of beneficial interest, shares authorized	100,000,000	100,000,000
Common shares of beneficial interest, shares issued	69,120,797	68,605,783
Common shares of beneficial interest, shares outstanding	69,120,797	68,605,783