Notes Payable (Details Textual) (USD $)	3 Months Ended			6 Months Ended
	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Notes Payable (Additional Textual) [Abstract]
Notes payable	$ 144,198,000	$ 145,364,000		$ 144,198,000
Notes Payable, net of premium	143,800,000	145,000,000		143,800,000
Fixed rate debt	112,900,000	113,800,000		112,900,000
Fixed rate debt, notes payable	79.00%	79.00%		79.00%
Variable rate debt	30,900,000	31,100,000		30,900,000
Variable rate debt, notes payable	21.00%	21.00%		21.00%
Deferred financing costs	1,500,000	1,700,000		(18,000)	(974,000)
Deferred financing costs	$ 2,100,000		$ 1,600,000	$ 211,000	$ 290,000
Fixed and variable rate secured mortgage loans with average effective interest rate	5.45%	5.45%		5.45%
Fixed rate debt, weighted average interest rate	5.35%	5.35%		5.35%
Variable rate debt, weighted average interest rate	5.83%	5.83%		5.83%
Maximum [Member]
Notes Payable (Additional Textual) [Abstract]
Fixed and variable rate secured mortgage loans with average effective interest rate	6.50%	6.50%		6.50%
Minimum [Member]
Notes Payable (Additional Textual) [Abstract]
Fixed and variable rate secured mortgage loans with average effective interest rate	2.80%	2.80%		2.80%