Mortgage Loans On Real Estate (Schedule Of Mortgage Loans On Real Estate) (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]      
Face Amount of Mortgages or Maximum Available Credit $ 41,695    
Carrying Amount of Mortgages $ 45,242 $ 45,734
Borrower A [Member] | Land [Member]      
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]      
Interest Accrual Rate 5.85%    
Interest Payment Rate 5.85%    
Final Maturity Date Jul. 21, 2019    
Periodic Payment Terms P&I    
Face Amount of Mortgages or Maximum Available Credit $ 41,695    
Carrying Amount of Mortgages $ 45,242