Investments In Unconsolidated Real Estate Entities (Schedule Of Investments In Real Estate Entities And Equity In Earnings Of Real Estate Entities) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Investments in Unconsolidated Real Estate Entities	$ 753,358		$ 753,358		$ 767,816
Equity in Earnings of Unconsolidated Real Estate Entities	17,655	$ 18,914	41,623	$ 36,586
PSB [Member]
Schedule of Equity Method Investments [Line Items]
Investments in Unconsolidated Real Estate Entities	432,466		432,466		427,875
Equity in Earnings of Unconsolidated Real Estate Entities	13,228	14,864	34,965	28,584
Shurgard [Member]
Schedule of Equity Method Investments [Line Items]
Investments in Unconsolidated Real Estate Entities	320,892		320,892		$ 339,941
Equity in Earnings of Unconsolidated Real Estate Entities	$ 4,427	$ 4,050	$ 6,658	$ 8,002

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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