v2.4.0.6
Assets Held for Sale and Discontinued Operations (Details Textual)
6 Months Ended 12 Months Ended
Jun. 30, 2012
sqft
Property
Dec. 31, 2011
sqft
Property
Assets Held for Sale and Discontinued Operations (Textual)[Abstract]    
Properties classified as held for sale 5  
Number of properties sold to third parties 95 94
Net square feet sold to third parties 11,900,000 10,700,000