Write-Off of Abandoned Development Projects and Demolition Costs (Details Textual) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Write-off of Abandoned Development Projects and Demolition Costs [Abstract]
Write-offs of abandoned development projects and demolition costs	$ 0	$ 456,000	$ 5,778,000	$ 1,389,000
Write-offs of abandoned development projects and demolition costs of unconsolidated entities	$ 0	$ 0	$ 10,191,000	$ 0