Fair Value Measurements (Schedule Of Estimates Of Fair Value Of Financial Instruments) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets:
Securities available-for-sale	$ 1,185,245	$ 1,178,789
Marketable equity securities	27,182	27,372
Net loans	3,522,647	3,597,570
Accrued interest receivable	16,231	15,793
Liabilities:
Deposits	4,796,835	4,652,216
Carrying Amount
Assets:
Cash and cash equivalents	756,799	528,659
Securities available-for-sale	1,185,245	1,178,789
Marketable equity securities	11,757	11,839
Net loans	3,522,647	3,597,570
Accrued interest receivable	16,231	15,793
Derivative assets	33,446	53,166
Liabilities:
Deposits	4,796,835	4,652,216
Short-term debt	316,003	295,956
Accrued interest payable	1,169	1,586
Derivative liabilities	29,773	53,288
Fair Value
Assets:
Cash and cash equivalents	756,799	528,659
Securities available-for-sale	1,185,245	1,178,789
Marketable equity securities	11,757	11,839
Net loans	3,473,330	3,578,013
Accrued interest receivable	16,231	15,793
Derivative assets	33,446	53,166
Liabilities:
Deposits	4,805,356	4,665,905
Short-term debt	316,003	295,956
Accrued interest payable	1,169	1,586
Derivative liabilities	29,773	53,288
Level 1
Assets:
Cash and cash equivalents	756,799	528,659
Securities available-for-sale	0	0
Marketable equity securities	6,726	6,800
Net loans	0	0
Accrued interest receivable	16,231	15,793
Derivative assets	0	0
Liabilities:
Deposits	3,586,962	3,392,194
Short-term debt	0	0
Accrued interest payable	1,169	1,586
Derivative liabilities	0	0
Level 2
Assets:
Cash and cash equivalents	0	0
Securities available-for-sale	1,176,631	1,169,954
Marketable equity securities	5,031	5,039
Net loans	0	0
Accrued interest receivable	0	0
Derivative assets	33,446	53,166
Liabilities:
Deposits	1,218,394	1,273,711
Short-term debt	316,003	295,956
Accrued interest payable	0	0
Derivative liabilities	29,773	53,288
Level 3
Assets:
Cash and cash equivalents	0	0
Securities available-for-sale	8,614	8,835
Marketable equity securities	0	0
Net loans	3,473,330	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

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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