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Fair Value Measurements (Carrying Amount, Estimated Fair Value, And Placement In Fair Value Hierarchy Of Financial Instruments) (Details) - USD ($) $ in Thousands		Dec. 31, 2016	Dec. 31, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities available for sale		$ 539,926	$ 544,395
Securities held to maturity, fair value		539,991	490,064
Carrying Amount [Member] | Level 1 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents		71,277	60,121
Accrued interest receivable		9,192	8,609
Non-maturity deposits		2,292,706	2,093,513
Short-term borrowings		331,500	293,100
Accrued interest payable		5,394	4,676
Carrying Amount [Member] | Level 2 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities available for sale		539,926	544,395
Securities held to maturity, fair value		543,338	485,717
Loans held for sale		1,050	1,430
Loans		2,308,326	2,055,192
FHLB and FRB stock		21,780	19,991
Time deposits		702,516	637,018
Long-term borrowings		39,061	38,990
Carrying Amount [Member] | Level 3 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	[1]	901	1,485
Estimated Fair Value [Member] | Level 1 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents		71,277	60,121
Accrued interest receivable		9,192	8,609
Non-maturity deposits		2,292,706	2,093,513
Short-term borrowings		331,500	293,100
Accrued interest payable		5,394	4,676
Estimated Fair Value [Member] | Level 2 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities available for sale		539,926	544,395
Securities held to maturity, fair value		539,991	490,064
Loans held for sale		1,050	1,430
Loans		2,285,146	2,046,235
FHLB and FRB stock		21,780	19,991
Time deposits		701,097	636,159
Long-term borrowings		40,701	40,313
Estimated Fair Value [Member] | Level 3 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	[1]	$ 901	$ 1,485
[1] Comprised of collateral dependent impaired loans.

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Non-Maturity Deposits Fair Value Disclosure

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- Definition

Fair value portion of liabilities incurred for goods and services received that are used in an entity's business and related party payables.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6506951

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-Name Accounting Standards Codification
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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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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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Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

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Fair value of investments in debt securities classified as held-to-maturity.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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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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-Publisher FASB
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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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This element represents the portion of the balance sheet assertion valued at fair value by the entity 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. This item represents the amount of short-term debt existing as of the balance sheet date.

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