Real Estate Facilities (Schedule Of Real Estate Activities) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Real Estate Facilities [Abstract]
Beginning balance (Operating facilities, at cost)		$ 16,289,146
Capital expenditures to maintain real estate facilities		95,629
Acquisitions		243,378
Dispositions		(282)
Developed or expanded facilities opened for operation		69,975
Ending balance (Operating facilities, at cost)	$ 16,697,846	16,697,846
Beginning balance (Accumulated depreciation)		(6,623,475)
Depreciation expense		(257,883)
Ending balance (Accumulated depreciation)	(6,881,358)	(6,881,358)
Beginning balance (Construction in process)		141,934
Costs incurred to develop and expand real estate facilities		84,649
Write-off of cancelled projects	(3,200)	(3,226)
Developed or expanded facilities opened for operations		(69,975)
Ending balance (Construction in process)	153,382	153,382
Total real estate facilities at June 30, 2020	$ 9,969,870	$ 9,969,870	$ 9,807,605