Property And Equipment (Summary Of Investment And Development Property) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Investment and development property	$ 29,839	$ 114,024
Land [Member]
Property, Plant and Equipment [Line Items]
Investment and development property	23,827	24,446
Building [Member]
Property, Plant and Equipment [Line Items]
Investment and development property		1,900
Construction-In-Progress (Including Capitalized Interest) [Member]
Property, Plant and Equipment [Line Items]
Investment and development property	$ 6,012	$ 87,678