Mortgages, Loans Payable And Other Obligatons (Schedule Of Principal Payments) (Details) - USD ($)
$ in Thousands
Jan. 31, 2018
Dec. 31, 2017
Mortgages, Loans Payabes And Other Obligations [Line Items]    
Scheduled Amortization, 2018 [1]   $ 6,977
Scheduled Amortization, 2019   665
Scheduled Amortization, 2020   2,903
Scheduled Amortization, 2021   3,227
Scheduled Amortization, 2022   3,284
Scheduled Amortization, Thereafter   10,642
Scheduled Amortization, Sub-total   27,698
Adjustment for unamortized debt discount/premium, net December 31, 2017   (3,505)
Scheduled Amortization, Unamortized mark to market   4,987
Unamortized deferred financing costs   (13,038)
Scheduled Amortization, Total   16,142
Principal Maturities, 2018 [1]   275,210
Principal Maturities, 2019   576,489
Principal Maturities, 2020   325,000
Principal Maturities, 2021   318,800
Principal Maturities, 2022   300,000
Principal Maturities, Thereafter   997,927
Principal Maturities, Sub-total   2,793,426
Principal Maturities, Total   2,793,426
Total, 2018 [1]   282,187
Total, 2019   577,154
Total, 2020   327,903
Total, 2021   322,027
Total, 2022   303,284
Total, Thereafter   1,008,569
Total, Sub-total   2,821,124
Adjustment for unamortized debt discount/premium, net December 31, 2017   (3,505)
Total, Unamortized mark to market   4,987
Total, Unamortized deferred financing costs   (13,038)
Total senior unsecured notes, net   $ 2,809,568
Subsequent Event [Member]    
Mortgages, Loans Payabes And Other Obligations [Line Items]    
Mortgage payable amount $ 209,000  
[1] Includes a mortgage payable amount of approximately $209 million that the Company prepaid in January 2018.