Accumulated Other Comprehensive Income (Loss) (Summary Of Changes In Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ 1,187
Other comprehensive income	3,090	$ 2,943
Ending balance	4,277
Unrealized gains and losses on available-for-sale securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	1,187	(5,020)
Other comprehensive income (loss) before reclassification	3,120	2,943
Other comprehensive income	3,090	2,943
Ending balance	4,277	(2,077)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income	3,090	2,943
Amount Reclassified From Accumulated Other Comprehensive Income (Loss) [Member] | Unrealized gains and losses on available-for-sale securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amount reclassified from accumulated other comprehensive (income) loss	$ (30)	$ 0