Deferred Charges, Goodwill And Other Assets, Net (Schedule Of Deferred Charges, Goodwill And Other Assets) (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Dec. 31, 2016
Deferred Charges, Goodwill And Other Assets [Line Items]          
Deferred leasing costs $ 210,797   $ 210,797   $ 220,947
Deferred financing costs - unsecured revolving credit facility [1] 4,945   4,945   5,400
Deferred charges, gross 215,742   215,742   226,347
Accumulated amortization (98,205)   (98,205)   (107,359)
Deferred charges, net 117,537   117,537   118,988
Notes receivable [2] 4,805   4,805   13,251
In-place lease values, related intangibles and other assets, net 120,440   120,440   72,046
Goodwill [3] 2,945   2,945   2,945
Prepaid expenses and other assets, net [4] 71,257   71,257   60,720
Total deferred charges, goodwill and other assets, net 316,984   316,984   $ 267,950
Lease revenue 133,017 $ 124,223 254,272 $ 250,610  
Interest-Free Notes Receivable [Member]          
Deferred Charges, Goodwill And Other Assets [Line Items]          
Notes receivable $ 2,700   $ 2,700    
Mortgage loan, maturity date     Apr. 01, 2023    
[1] Pursuant to recently issued accounting standards, deferred financing costs related to all other debt liabilities (other than for the unsecured revolving credit facility) are netted against those debt liabilities for all periods presented. See Note 2: Significant Accounting Policies - Deferred Financing Costs.
[2] Includes as of June 30, 2017, an interest-free note receivable with a net present value of $2.7 million which matures in April 2023. The Company believes this balance is fully collectible.
[3] All goodwill is attributable to the Company's Multi-family Services segment.
[4] Includes $15.1 million of proceeds from property sales held by a qualified intermediary as of June 30, 2017.