ACQUISITION AND DISPOSITION OF PROPERTIES AND DISCONTINUED OPERATIONS Dispositions (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended			36 Months Ended
	Dec. 31, 2011 sqft	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2011 sqft
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sales Price	$ 62,940	$ 0	$ 11,956	$ 76,921
Gain (Loss)	46,830	0	7,143	53,973
GLA	1,784,388			1,784,388
Fifteen Kroger/Safeway Locations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sales Price	17,490
Gain (Loss)	14,645
GLA	617,276			617,276
Granville Centre [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sales Price	2,250
Gain (Loss)	(313)
GLA	134,997			134,997
Ledgewood Mall [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sales Price	37,000
Gain (Loss)	28,576
GLA	517,151			517,151
Oakbrook [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sales Price	8,200
Gain (Loss)	3,922
GLA	112,000			112,000
Blackman Plaza [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sales Price			2,500
Gain (Loss)			1,506
GLA			125,264
Six Kroger Locations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sales Price			9,481
Gain (Loss)			$ 5,637
GLA			277,700