Risk Management and Use of Derivative Financial Instruments (Details 2) (Designated as hedging, USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013
Derivative
Fair Value	$ (205)
"Rollercoaster" swap | LIBOR | 1-month | May | 2012
Derivative
Notional Amount	9,750
Effective Interest Rates	5.00%
Effective Date	May 01, 2012
Expiration Date	May 31, 2015
Fair Value	(104)
"Pay-fixed" swap | LIBOR | 1-month
Derivative
Notional Amount	33,000
Effective Date	Aug. 01, 2013
Expiration Date	Aug. 31, 2018
"Pay-fixed" swap | LIBOR | 1-month | March | 2013
Derivative
Notional Amount	19,350
Effective Interest Rates	4.10%
Effective Date	Mar. 01, 2013
Expiration Date	Mar. 31, 2017
Fair Value	(9)
"Pay-fixed" swap | LIBOR | 1-month | July | 2013
Derivative
Notional Amount	44,000
Effective Interest Rates	4.10%
Effective Date	Jul. 01, 2013
Expiration Date	Jul. 01, 2018
Fair Value	(597)
"Pay-fixed" swap | LIBOR | 1-month | December | 2012
Derivative
Notional Amount	51,500
Effective Interest Rates	4.60%
Effective Date	Dec. 01, 2012
Expiration Date	Dec. 31, 2017
Fair Value	$ 505