Subsequent Events (Details Textual) (USD $) In Thousands, unless otherwise specified	2 Months Ended	12 Months Ended
	Feb. 28, 2012 sqft IndustrialProperty	Dec. 31, 2011 sqft
Subsequent Events (Textual) [Abstract]
Number of industrial property sold	0
Area of industrial property	400,000	66,300,000
Ownership percentage purchased	85.00%	85.00%
Cash Paid in Acquisition	$ 8,324	$ 5,277
Mortgage loan payable assumed in conjunction with a property acquisition	12,026	24,417
Number of industrial property acquired	1
Amount of repurchased and retired senior unsecured notes maturing in two thousand twenty eight	430
Amount of payment of senior unsecured notes maturing in two thousand twenty eight	$ 406