Impairment (Schedule Of Impairment Charges) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Asset Impairment [Line Items]
Other				$ 165		$ 0		$ 0
Total reported in continuing operations				2,579		9,585		49,671
Total impairment charges				2,815		15,436		75,874
Equity in loss of real estate joint ventures and partnerships, net				35,112		(1,558)		7,834
Net loss attributable to noncontrolling interests	37,700			44,894		5,781		1,118
Net impact of impairment charges		24,900	10,000	3,210		35,382		78,437
Tax Increment Revenue Bonds [Member]
Asset Impairment [Line Items]
Impairment losses related to tax increment revenue bonds				0	[1]	0	[1]	18,737	[1]
Land Held For Development And Undeveloped Land [Member]
Asset Impairment [Line Items]
Impairment losses related to property				2,358	[2]	0	[2]	23,646	[2]
Property Marketed For Sale Or Sold [Member]
Asset Impairment [Line Items]
Impairment losses related to property				56	[3]	2,977	[3]	5,536	[3]
Investments In Real Estate Joint Ventures And Partnerships [Member]
Asset Impairment [Line Items]
Impairment losses related to partially owned real estate joint ventures and partnerships				0	[4]	6,608	[4]	1,752	[4]
Property Held For Sale Or Sold [Member]
Asset Impairment [Line Items]
Impairment losses related to property				236	[5]	5,851	[5]	26,203	[5]
Impairment Charges At Equity In Loss Of Real Estate Joint Ventures And Partnerships [Member]
Asset Impairment [Line Items]
Equity in loss of real estate joint ventures and partnerships, net				395		19,946		7,022
Impairment Charges At Net Loss Attributable To Noncontrolling Interests [Member]
Asset Impairment [Line Items]
Net loss attributable to noncontrolling interests				$ 0		$ 0		$ (4,459)

[1] During 2011, the tax increment revenue bonds were remarketed by the Agency. All of the outstanding bonds were recalled, and new bonds were issued. We recorded an $18.7 million net credit loss on the exchange of bonds associated with our investment in the tax increment revenue bonds.

[2] Impairment was prompted by changes in management's plans for these properties, recent comparable market transactions and/or a change in market conditions.

[3] These charges resulted from changes in management’s plans for these properties, primarily the marketing of these properties for sale. Also, included in this caption are impairments associated with dispositions that did not qualify to be reported in discontinued operations.

[4] Amounts reported in 2012 were based on third party offers to buy our interests in industrial real estate joint ventures. Amounts reported in 2011 relate to market conditions.

[5] Amounts reported were based on third party offers.