Fair Value Measurements (Schedule Of Estimates Of Fair Value Of Financial Instruments) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets:
Estimated Fair Value	$ 1,372,077	$ 1,176,797
Marketable equity securities	25,497	29,364
Net loans	3,503,174	3,597,570
Accrued interest receivable	16,224	15,793
Liabilities:
Deposits	4,887,476	4,652,216
Carrying Amount
Assets:
Cash and cash equivalents	639,549	528,659
Estimated Fair Value	1,372,077	1,176,797
Marketable equity securities	9,159	11,839
Net loans	3,503,174	3,597,570
Accrued interest receivable	16,224	15,793
Derivative assets	33,076	53,166
Liabilities:
Deposits	4,887,476	4,652,216
Short-term debt	296,642	295,956
Accrued interest payable	815	1,586
Derivative liabilities	29,985	53,288
Fair Value
Assets:
Cash and cash equivalents	639,549	528,659
Estimated Fair Value	1,372,077	1,176,797
Marketable equity securities	9,159	11,839
Net loans	3,422,601	3,578,013
Accrued interest receivable	16,224	15,793
Derivative assets	33,076	53,166
Liabilities:
Deposits	4,890,521	4,665,905
Short-term debt	296,642	295,956
Accrued interest payable	815	1,586
Derivative liabilities	29,985	53,288
Level 1
Assets:
Cash and cash equivalents	639,549	528,659
Estimated Fair Value	0	0
Marketable equity securities	4,089	6,800
Net loans	0	0
Accrued interest receivable	16,224	15,793
Derivative assets	0	0
Liabilities:
Deposits	3,783,407	3,392,194
Short-term debt	0	0
Accrued interest payable	815	1,586
Derivative liabilities	0	0
Level 2
Assets:
Cash and cash equivalents	0	0
Estimated Fair Value	1,368,278	1,167,962
Marketable equity securities	5,070	5,039
Net loans	0	0
Accrued interest receivable	0	0
Derivative assets	33,076	53,166
Liabilities:
Deposits	1,107,114	1,273,711
Short-term debt	296,642	295,956
Accrued interest payable	0	0
Derivative liabilities	29,985	53,288
Level 3
Assets:
Cash and cash equivalents	0	0
Estimated Fair Value	3,799	8,835
Marketable equity securities	0	0
Net loans	3,422,601	3,578,013
Accrued interest receivable	0	0
Derivative assets	0	0
Liabilities:
Deposits	0	0
Short-term debt	0	0
Accrued interest payable	0	0
Derivative liabilities	$ 0	$ 0