Property Transactions Property Transactions (Discontinued Operations) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Discontinued Operations [Line Items]
Income (Loss) from Discontinued Operations	$ (86)	$ (9,749)
Gain (Loss) on Disposal of Discontinued Operation	95	86
Segment, Discontinued Operations [Member]
Discontinued Operations [Line Items]
Rental property revenues	2	7,919
Fee Income	74	4,710
Other Income	0	192
Rental property operating expenses	(105)	(2,279)
Reimbursed Expenses	0	(2,303)
General and Administrative Expense	(53)	(1,997)
Depreciation and amortization	0	(3,741)
Impairment of Real Estate	0	12,233
Discontinued Operations Other Expense	4	17
Income (Loss) from Discontinued Operations	(86)	(9,749)
King Mill Distribution Park Building Three [Member]
Discontinued Operations [Line Items]
Gain (Loss) on Disposal of Discontinued Operation	119	87
Cosmopolitan Center [Member]
Discontinued Operations [Line Items]
Gain (Loss) on Disposal of Discontinued Operation	(23)	0
Other Discontinued Operations [Member]
Discontinued Operations [Line Items]
Gain (Loss) on Disposal of Discontinued Operation	$ (1)	$ (1)