Fair Value Measurements (Schedule Of Fair Value Of Notes Receivable From Real Estate Joint Ventures And Partnerships) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying value	$ 90,385	$ 149,204
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value	$ 93,257	$ 153,532

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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+ Details