Basis Of Presentation And Summary Of Significant Accounting Policies (Carrying Value Of Note Receivable, Indebtedness And Corresponding Estimate Of Fair Value) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Summary Of Significant Accounting Policies [Line Items]
Related party note receivable	$ 80,000	$ 80,000
Note receivable	19,844	19,468
Mortgage notes payable, net	2,952,006	2,964,572
Unsecured senior notes, net	8,387,913	7,544,697
Unsecured line of credit	0	0
Unsecured term loan, net	498,819	498,488
Carrying Amount [Member]
Summary Of Significant Accounting Policies [Line Items]
Related party note receivable	80,000	80,000
Note receivable	19,844	19,468
Note and Related Party Receivables	99,844	99,468
Mortgage notes payable, net	2,952,006	2,964,572
Unsecured senior notes, net	8,387,913	7,544,697
Unsecured line of credit	0	0
Unsecured term loan, net	498,819	498,488
Total	11,838,738	11,007,757
Estimated Fair Value [Member]
Summary Of Significant Accounting Policies [Line Items]
Related party note receivable	81,337	80,000
Note receivable	18,507	19,468
Note and Related Party Receivables	99,844	99,468
Mortgage notes payable, net	3,052,922	2,903,925
Unsecured senior notes, net	8,848,468	7,469,338
Unsecured line of credit	0	0
Unsecured term loan, net	500,618	500,783
Total	$ 12,402,008	$ 10,874,046