Fair Value Measurements (Carrying Amount, Estimated Fair Value, and Placement in Fair Value Hierarchy of Financial Instruments) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Securities available for sale	$ 444,845	$ 417,917
Securities held to maturity, fair value	354,571	363,259
Carrying Amount [Member] \| Level 1 Inputs [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash and cash equivalents	152,168	112,947
Accrued interest receivable	12,198	11,308
Non-maturity deposits	2,727,840	2,375,486
Short-term borrowings	109,500	275,500
Accrued interest payable	11,053	10,942
Carrying Amount [Member] \| Level 2 Inputs [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Securities available for sale	444,845	417,917
Securities held to maturity, fair value	346,239	359,000
Loans held for sale	3,822	4,224
Loans	3,181,831	3,186,875
FHLB and FRB stock	13,167	20,637
Time deposits	1,059,345	1,180,189
Long-term borrowings	32,291	39,273
Carrying Amount [Member] \| Level 2 Inputs [Member] \| Cash Flow Hedging [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, assets	2
Carrying Amount [Member] \| Level 2 Inputs [Member] \| Interest Rate Products [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, assets	19,921	6,419
Derivative instruments, liabilities	20,431	6,720
Carrying Amount [Member] \| Level 2 Inputs [Member] \| Credit Contract [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, assets	32	13
Derivative instruments, liabilities	42	18
Carrying Amount [Member] \| Level 2 Inputs [Member] \| Mortgage Banking [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, assets	259	119
Derivative instruments, liabilities	120	7
Carrying Amount [Member] \| Level 3 Inputs [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Loans	12,040	3,630
Estimated Fair Value [Member] \| Level 1 Inputs [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash and cash equivalents	152,168	112,947
Accrued interest receivable	12,198	11,308
Non-maturity deposits	2,727,840	2,375,486
Short-term borrowings	109,500	275,500
Accrued interest payable	11,053	10,942
Estimated Fair Value [Member] \| Level 2 Inputs [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Securities available for sale	444,845	417,917
Securities held to maturity, fair value	354,571	363,259
Loans held for sale	3,822	4,224
Loans	3,208,870	3,201,814
FHLB and FRB stock	13,167	20,637
Time deposits	1,062,306	1,179,991
Long-term borrowings	42,653	41,083
Estimated Fair Value [Member] \| Level 2 Inputs [Member] \| Cash Flow Hedging [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, assets	2
Estimated Fair Value [Member] \| Level 2 Inputs [Member] \| Interest Rate Products [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, assets	19,921	6,419
Derivative instruments, liabilities	20,431	6,720
Estimated Fair Value [Member] \| Level 2 Inputs [Member] \| Credit Contract [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, assets	32	13
Derivative instruments, liabilities	42	18
Estimated Fair Value [Member] \| Level 2 Inputs [Member] \| Mortgage Banking [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, assets	259	119
Derivative instruments, liabilities	120	7
Estimated Fair Value [Member] \| Level 3 Inputs [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Loans	$ 12,040	$ 3,630

Non-Maturity Deposits Fair Value Disclosure

No definition available.

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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
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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.

+ References

No definition available.

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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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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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-Publisher FASB
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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.

+ References

No definition available.

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- Definition

Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

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No definition available.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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-Publisher FASB
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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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-Paragraph 1
-Subparagraph (SX 210.5-02.8)
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- Definition

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

+ References

No definition available.

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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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.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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