Fair Value (Fair Value Of Financial Instruments) (Details) - USD ($)	6 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and money market instruments	$ 259,505,000	$ 167,214,000
Investment securities	1,343,385,000	1,354,843,000
Federal Home Loan Bank Stock	35,280,000	43,388,000
Federal Reserve Bank Stock	10,811,000	8,225,000
Loans Held-for-sale, Fair Value Disclosure	13,033,000	4,158,000
Derivative Assets	361,000	87,000
Impaired Loan Fair Value	4,212,000	6,399,000
Other loans	6,294,891,000	5,570,136,000
Loans receivable, net	6,312,497,000	5,580,780,000
Time deposits	1,133,461,000	1,044,620,000
Other	3,996,000	1,267,000
Total deposits	1,137,457,000	1,045,887,000
Short-term borrowings	180,578,000	221,966,000
Long-term debt	407,248,000	400,203,000
Subordinated debentures/notes	13,566,000	12,959,000
Unrealized Gain (Loss) on Cash Flow Hedging Instruments	642,000
Equity Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	1,832,000	1,649,000
Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	226,000	226,000
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and money market instruments	259,505,000	167,214,000
Investment securities	1,329,200,000	1,355,229,000
Loans Held-for-sale, Fair Value Disclosure	13,033,000	4,158,000
Derivative Assets	361,000	87,000
Impaired Loan Fair Value	4,212,000	6,399,000
Other loans	6,305,128,000	5,629,976,000
Loans receivable, net	6,322,734,000	5,640,620,000
Time deposits	1,131,310,000	1,043,177,000
Other	3,996,000	1,267,000
Total deposits	1,135,306,000	1,044,444,000
Short-term borrowings	180,578,000	221,966,000
Long-term debt	400,000,000	400,000,000
Subordinated debentures/notes	15,000,000	15,000,000
Reported Value Measurement [Member] \| Equity Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	1,832,000	1,649,000
Reported Value Measurement [Member] \| Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	226,000	226,000
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	361,000	87,000
Impaired Loan Fair Value		6,399,000
Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and money market instruments	259,505,000	167,214,000
Derivative Assets	0	0
Other	3,996,000	1,267,000
Total deposits	3,996,000	1,267,000
Fair Value, Inputs, Level 1 [Member] \| Equity Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	1,399,000	1,225,000
Fair Value, Inputs, Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	1,343,385,000	1,354,843,000
Loans Held-for-sale, Fair Value Disclosure	13,033,000	4,158,000
Derivative Assets	361,000	87,000
Loans receivable, net	13,394,000	4,245,000
Time deposits	1,133,461,000	1,044,620,000
Total deposits	1,133,461,000	1,044,620,000
Short-term borrowings	180,578,000	221,966,000
Long-term debt	407,248,000	400,203,000
Subordinated debentures/notes	13,566,000	12,959,000
Fair Value, Inputs, Level 2 [Member] \| Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unrealized Gain (Loss) on Cash Flow Hedging Instruments	642,000
Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	0	0
Impaired Loan Fair Value	4,212,000	6,399,000
Other loans	6,294,891,000	5,570,136,000
Loans receivable, net	6,299,103,000	5,576,535,000
Fair Value, Inputs, Level 3 [Member] \| Equity Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	433,000	424,000
Fair Value, Inputs, Level 3 [Member] \| Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	$ 226,000	$ 226,000

Impaired Loan Fair Value

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Short Term Borrowings Fair Value

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- Definition

Time Deposits Fair Value

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- Definition

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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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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No definition available.

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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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Fair value, after the effects of master netting arrangements, of a financial liability or 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 liabilities not subject to a master netting arrangement and not elected to be offset.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Federal Reserve Bank stock represents an equity interest in the Federal Reserve Bank. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Fair value portion of other assets.

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Fair value portion of other liabilities.

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Amount of unrealized gain (loss) related to derivatives designated as cash flow hedging instruments, recorded in results of operations to the extent that the cash flow hedge is determined to be ineffective.

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