Prepaid Expenses and Other Current Assets and Other Assets (Schedule Of Other Assets) (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
Prepaid Expenses and Other Current Assets and Other Assets [Abstract]
Prepaid ground rent				$ 263,694
Straight-line rent receivable			$ 326,535	322,073
Loan receivables			62,317	49,255
Deferred lease costs, net			4,258	27,020
Deferred tax asset - long term			10,265	18,330
Other			48,099	41,661
Total other assets	[1]		$ 451,474	$ 722,033
Write-off of deferred lease costs		$ 23,300

[1] On January 1, 2019, the Company adopted ASU 2016-02 which requires lessees to recognize a right-of-use asset and a lease liability. Upon adoption, certain assets and liabilities were reclassified to Right-of-use assets, net and lease liabilities in accordance with provisions of ASU 2016-02. See Note 1 for further discussion.