Discontinued Operations (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended					9 Months Ended			3 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Mar. 31, 2011 Oak Hollow Mall, High Point [Member]	Dec. 31, 2011 Westridge Square [Member]	Mar. 31, 2012 Settlers Ridge Phase II [Member]	Sep. 30, 2011 Settlers Ridge Phase II [Member]	Mar. 31, 2012 Oak Hollow Square [Member]	Dec. 31, 2011 Oak Hollow Square [Member]	Sep. 30, 2012 Hickory Hollow Mall [Member]	Sep. 30, 2012 Towne Mall [Member]	Sep. 30, 2012 Massard Crossing [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real Estate Investment Property, Net		$ 6,143,896				$ 6,143,896		$ 6,005,670							$ 9,007	$ 1,311
Fair value of real estate investment		27,043				27,043									960	892
Gross sales price		7,803							9,000	26,125	19,144		14,247
Extinguishment of Debt, Amount	106,895	121,980	30,763	381,568					40,281
Gain on extinguishment of debt		178			0	178	581		31,434
Net sales price		7,432								25,768	18,951		13,796
Gain on discontinued operations										160	883						98
Loss on impairment of real estate		21,654			51,304	21,654	51,304		2,746			4,457	255	729	8,047	419
Revenues of discontinued operations		$ 229			$ 2,747	$ 3,164	$ 8,247