Recent Transactions (Schedule Of Properties Which Commenced Initial Operations) (Details)
12 Months Ended
Dec. 31, 2020
USD ($)
item
Dec. 31, 2019
USD ($)
item
Real Estate Properties [Line Items]    
Total number of Apartment Units | item 326 208
Total Development Costs Incurred | $ $ 103,993,000 $ 105,477,000
Emery At Overlook Ridge [Member]    
Real Estate Properties [Line Items]    
Total number of Apartment Units | item 326  
Total Development Costs Incurred | $ $ 103,993,000  
Autograph Collection By Marriott (Phase II) [Member]    
Real Estate Properties [Line Items]    
Total number of Apartment Units | item   208
Total Development Costs Incurred | $   $ 105,477,000