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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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