Other Investment Securities (Schedule Of Other Investment Securities) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Schedule of Investments [Line Items]
equity investment shares sold			99,646
Proceeds from Sale of Federal Home Loan Bank Stock			$ 10,000,000.0
equity investment purchased, shares			128,553
Federal Home Loan Bank Stock	$ 33,424,000		$ 33,424,000		$ 43,388,000
Federal Reserve Bank Stock	14,653,000		14,653,000		8,225,000
Equity investments carried at fair value	1,889,000		1,889,000		1,649,000
Equity Method Investments	2,689,000		2,689,000		2,589,000
Alternative Investment	15,989,000		15,989,000		17,065,000
Other investment securities	68,644,000		68,644,000		72,916,000
Gain on equity securities, net	3,335,000	$ 89,000	5,309,000	$ 4,633,000
Alternative Investment, income recognized	3,300,000	415,000	5,100,000	1,200,000
Equity Securities, FV-NI, Unrealized Gain				3,500,000
securities purchased [Member]
Schedule of Investments [Line Items]
Federal Reserve Bank Stock	6,400,000		6,400,000
Equity Securities [Member]
Schedule of Investments [Line Items]
Gain on equity securities, net	58,000	$ (326,000)
Investments [Member]
Schedule of Investments [Line Items]
Gain on equity securities, net			241,000	$ (33,000)
Fair Value Measured at Net Asset Value Per Share [Member]
Schedule of Investments [Line Items]
Alternative Investment	$ 12,400,000		$ 12,400,000		$ 11,000,000.0