Beneficiaries Equity of the Parent Company (Details Textuals) (Details) - USD ($)		3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 15, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014	Oct. 19, 2015	Sep. 15, 2015	Jul. 22, 2015	Nov. 05, 2013
Class of Stock [Line Items]
Net income from continuing operations attributable to non-controlling interests		$ 161,000	$ 108,000	$ 221,000	$ 47,000
Antidilutive Securities Excluded from Computation of Earnings Per Share				1,535,102	1,721,905
Distributions Payable		$ 28,318,000		$ 28,318,000		$ 28,871,000
Preferred Stock, Dividend Rate, Percentage				6.90%		6.90%
Dividends, Preferred Stock, Cash				$ 5,175,000	$ 5,175,000
Authorized Amount									$ 100,000,000.0
Number of Shares Authorized to be Repurchased		539,200		539,200
Repurchased and Retired, Shares				4,701,302
Share Price				$ 12.92
Repurchased and Retired, Value				$ 60,817,000
Series E Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Dividend Rate, Percentage				6.90%
Preferred Stock, Liquidation Preference Per Share		$ 25.00		$ 25.00
Offering Program [Member]
Class of Stock [Line Items]
Shares Authorized For Equity Offering Program										16,000,000
Remaining Shares Available For Sales		16,000,000		16,000,000
Dividend Declared [Member]
Class of Stock [Line Items]
Dividends Payable, Amount Per Share								$ 0.15
Dividend Paid [Member] | Subsequent Event [Member]
Class of Stock [Line Items]
Distributions Payable							$ 26,600,000
Dividend Paid [Member] | Subsequent Event [Member] | Series E Preferred Stock [Member]
Class of Stock [Line Items]
Dividends, Preferred Stock, Cash	$ 1,700,000
Maximum [Member] | Offering Program [Member]
Class of Stock [Line Items]
Fees and Commissions Percentage				2.00%