Property Transactions (Components of Income (Loss) from Discontinued Operations) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Document Fiscal Year Focus	2013
Components of Income (Loss) from Discontinued Operations
Gains (Losses) on Extinguishment of Debt	$ 0	$ (94)	$ 0
Income (loss) from discontinued operations	3,299	1,907	(189)
Discontinued Operations [Member]
Components of Income (Loss) from Discontinued Operations
Rental property revenues	10,552	33,918	51,985
Third party management and leasing revenues	76	16,364	19,359
Other income	40	3,557	209
Rental property expenses	(4,162)	(10,935)	(19,575)
Third party management and leasing expenses	(99)	(13,678)	(16,584)
Disposal Group, Including Discontinued Operation, Interest Expense	0	0	(1,107)
Impairment losses	0	(13,791)	(10,945)
Depreciation and amortization	(3,083)	(13,479)	(23,395)
Gains (Losses) on Extinguishment of Debt	0	0	(74)
Other	(25)	(49)	(62)
Income (loss) from discontinued operations	$ 3,299	$ 1,907	$ (189)