Investment Securities (Schedule Of Investment Securities) (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	$ 1,819,950	$ 1,854,852
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3,941	1,620
Securities Available-for-Sale, Gross Unrealized Holding Losses	109,451	122,776
Debt Securities, Available-for-sale	1,714,440	1,733,696
US States and Political Subdivisions Debt Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	422,398	423,285
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3,941	1,620
Securities Available-for-Sale, Gross Unrealized Holding Losses	14,333	18,194
Debt Securities, Available-for-sale	412,006	406,711
U.S. Government Sponsored Entities Asset-Backed Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	805,466	839,399
Securities Available-for-Sale, Gross Unrealized Holding Losses	75,205	82,638
Debt Securities, Available-for-sale	730,261	756,761
Corporate Debt Securities
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	17,650	17,650
Securities Available-for-Sale, Gross Unrealized Holding Losses	2,249	1,178
Debt Securities, Available-for-sale	15,401	16,472
Collateralized Loan Obligations
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	535,436	535,518
Securities Available-for-Sale, Gross Unrealized Holding Losses	16,008	18,979
Debt Securities, Available-for-sale	519,428	516,539
US Government Corporations and Agencies Securities
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	39,000	39,000
Securities Available-for-Sale, Gross Unrealized Holding Losses	1,656	1,787
Debt Securities, Available-for-sale	$ 37,344	$ 37,213