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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		Mar. 31, 2017	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities available for sale		$ 540,406	$ 539,926
Securities held to maturity, fair value		544,438	539,991
Carrying Amount [Member] | Level 1 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents		149,699	71,277
Accrued interest receivable		10,329	9,192
Non-maturity deposits		2,435,195	2,292,706
Short-term borrowings		303,300	331,500
Accrued interest payable		6,340	5,394
Carrying Amount [Member] | Level 2 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities available for sale		540,406	539,926
Securities held to maturity, fair value		545,381	543,338
Loans held for sale		2,097	1,050
Loans		2,369,777	2,308,326
FHLB and FRB stock		20,511	21,780
Time deposits		734,464	702,516
Long-term borrowings		39,078	39,061
Carrying Amount [Member] | Level 3 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	[1]	1,769	901
Estimated Fair Value [Member] | Level 1 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents		149,699	71,277
Accrued interest receivable		10,329	9,192
Non-maturity deposits		2,435,195	2,292,706
Short-term borrowings		303,300	331,500
Accrued interest payable		6,340	5,394
Estimated Fair Value [Member] | Level 2 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities available for sale		540,406	539,926
Securities held to maturity, fair value		544,438	539,991
Loans held for sale		2,097	1,050
Loans		2,343,479	2,285,146
FHLB and FRB stock		20,511	21,780
Time deposits		732,294	701,097
Long-term borrowings		41,518	40,701
Estimated Fair Value [Member] | Level 3 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	[1]	$ 1,769	$ 901
[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
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 14
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-Section S99
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-Section 45
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6935-107765

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 25
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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
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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.

+ References

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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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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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