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Fair Value Measurements (Assets Measured At Fair Value On A Recurring And Non-Recurring Basis) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	$ 510,197	$ 524,973
Collateral Dependent Impaired Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value	4,826
Loan Servicing Rights [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value	983
Other Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value	480
Measured On A Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	511,096	524,973
Liabilities at fair value	21	4
Measured On A Recurring Basis [Member] | Derivative instruments - credit contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities at fair value	21	4
Measured On A Recurring Basis [Member] | U.S. Government Agencies And Government Sponsored Enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	158,816	161,889
Measured On A Recurring Basis [Member] | Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	351,381	363,084
Measured On A Recurring Basis [Member] | Hedging Derivative Instruments, Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	899
Measured On A Recurring Basis [Member] | Level 1 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale
Liabilities at fair value
Measured On A Recurring Basis [Member] | Level 1 Inputs [Member] | Derivative instruments - credit contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities at fair value
Measured On A Recurring Basis [Member] | Level 1 Inputs [Member] | U.S. Government Agencies And Government Sponsored Enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale
Measured On A Recurring Basis [Member] | Level 1 Inputs [Member] | Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale
Measured On A Recurring Basis [Member] | Level 1 Inputs [Member] | Hedging Derivative Instruments, Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale
Measured On A Recurring Basis [Member] | Level 2 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	511,096	524,973
Liabilities at fair value	21	4
Measured On A Recurring Basis [Member] | Level 2 Inputs [Member] | Derivative instruments - credit contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities at fair value	21	4
Measured On A Recurring Basis [Member] | Level 2 Inputs [Member] | U.S. Government Agencies And Government Sponsored Enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	158,816	161,889
Measured On A Recurring Basis [Member] | Level 2 Inputs [Member] | Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	351,381	363,084
Measured On A Recurring Basis [Member] | Level 2 Inputs [Member] | Hedging Derivative Instruments, Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	899
Measured On A Recurring Basis [Member] | Level 3 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale
Liabilities at fair value
Measured On A Recurring Basis [Member] | Level 3 Inputs [Member] | Derivative instruments - credit contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities at fair value
Measured On A Recurring Basis [Member] | Level 3 Inputs [Member] | U.S. Government Agencies And Government Sponsored Enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale
Measured On A Recurring Basis [Member] | Level 3 Inputs [Member] | Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale
Measured On A Recurring Basis [Member] | Level 3 Inputs [Member] | Hedging Derivative Instruments, Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale
Measured On A Nonrecurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value	7,812	7,703
Measured On A Nonrecurring Basis [Member] | Loans Held For Sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value	1,523	2,718
Measured On A Nonrecurring Basis [Member] | Collateral Dependent Impaired Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value	4,826	3,847
Measured On A Nonrecurring Basis [Member] | Loan Servicing Rights [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value	983	990
Measured On A Nonrecurring Basis [Member] | Other Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value	480	148
Measured On A Nonrecurring Basis [Member] | Level 1 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 1 Inputs [Member] | Loans Held For Sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 1 Inputs [Member] | Collateral Dependent Impaired Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 1 Inputs [Member] | Loan Servicing Rights [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 1 Inputs [Member] | Other Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 2 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value	1,523	2,718
Measured On A Nonrecurring Basis [Member] | Level 2 Inputs [Member] | Loans Held For Sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value	1,523	2,718
Measured On A Nonrecurring Basis [Member] | Level 2 Inputs [Member] | Collateral Dependent Impaired Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 2 Inputs [Member] | Loan Servicing Rights [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 2 Inputs [Member] | Other Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 3 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value	6,289	4,985
Measured On A Nonrecurring Basis [Member] | Level 3 Inputs [Member] | Loans Held For Sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value
Measured On A Nonrecurring Basis [Member] | Level 3 Inputs [Member] | Collateral Dependent Impaired Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value	4,826	3,847
Measured On A Nonrecurring Basis [Member] | Level 3 Inputs [Member] | Loan Servicing Rights [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value	983	990
Measured On A Nonrecurring Basis [Member] | Level 3 Inputs [Member] | Other Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets at fair value	$ 480	$ 148

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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+ References

No definition available.

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