Stockholder's Equity (Details Textuals) (USD $)	12 Months Ended					3 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010 Series H Preferred Stock [Member]	Dec. 31, 2011 Series I Preferred Stock [Member]	Mar. 31, 2012 Series J Preferred Stock [Member]
Stockholders' Equity (Details) [Abstract]
Acquisitions of non controlling interests	$ (23,247,000)	$ 0	$ 0
Equity issued in acquisition of noncontrolling interest	1,108,917
Percentage of partnership owned	20.00%
Total purchase price	91,000,000
Transaction costs existing partnership	$ 2,732,000
Preferred Stock [Line Items]
Preferred stock, shares issued	0	11,500,000	14,375,000	349,854	14,375,000	11,500,000
Preferred stock balance issued average rate	0	0.065	0.065	0.06	0.065	0.065
Redemption date, preferred stock				Dec. 31, 2015		Mar. 07, 2017
Equivalent Number Of Common Stock On Conversion Of Preferred Shares					0.846
Initial conversion Price				$ 25	$ 59.1	$ 25
Liquidation value per preferred share				$ 25	$ 50