Fair Value (Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Assets:
Securities	$ 737,957	$ 740,994
Loans Held-for-Sale	6,628	6,719
Derivative Assets	2,232	1,564
Mortgage Servicing Rights	531	547
Derivative Liabilities	2,210	1,633
Obligations of State and Political Subdivisions
Assets:
Securities	272,753	273,309
MBS/CMO - Residential
Assets:
Securities	464,851	467,332
Equity Securities
Assets:
Securities	353	353
Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Securities	0	0
Loans Held-for-Sale	0	0
Derivative Assets	0	0
Mortgage Servicing Rights	0	0
Derivative Liabilities	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Obligations of State and Political Subdivisions
Assets:
Securities	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| MBS/CMO - Residential
Assets:
Securities	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Equity Securities
Assets:
Securities	0	0
Significant Other Observable Inputs (Level 2)
Assets:
Securities	732,433	734,992
Loans Held-for-Sale	6,628	6,719
Derivative Assets	2,232	1,564
Mortgage Servicing Rights	531	547
Derivative Liabilities	2,210	1,633
Significant Other Observable Inputs (Level 2) \| Obligations of State and Political Subdivisions
Assets:
Securities	267,582	267,660
Significant Other Observable Inputs (Level 2) \| MBS/CMO - Residential
Assets:
Securities	464,851	467,332
Significant Other Observable Inputs (Level 2) \| Equity Securities
Assets:
Securities	0	0
Significant Unobservable Inputs (Level 3)
Assets:
Securities	5,524	6,002
Loans Held-for-Sale	0	0
Derivative Assets	0	0
Mortgage Servicing Rights	0	0
Derivative Liabilities	0	0
Significant Unobservable Inputs (Level 3) \| Obligations of State and Political Subdivisions
Assets:
Securities	5,171	5,649
Significant Unobservable Inputs (Level 3) \| MBS/CMO - Residential
Assets:
Securities	0	0
Significant Unobservable Inputs (Level 3) \| Equity Securities
Assets:
Securities	$ 353	$ 353

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Fair value as of the balance sheet date of all derivative assets not designated as hedging instruments.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
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Fair value as of the balance sheet date of all derivative liabilities not designated as hedging instruments.

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

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

+ References

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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