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Loans (Summary Of Impaired Loans) (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2018 | Dec. 31, 2017
Financing Receivable, Impaired [Line Items] |  |  |
Recorded Investment, With no related allowance recorded | [1] | $ 1,828 | $ 2,219
Recorded Investment, With an allowance recorded | [1] | 5,416 | 6,381
Recorded Investment | [1] | 7,244 | 8,600
Unpaid Principal Balance, With no related allowance recorded | [1] | 2,344 | 2,954
Unpaid Principal Balance, With an allowance recorded | [1] | 5,508 | 6,381
Unpaid Principal Balance | [1] | 7,852 | 9,335
Related Allowance |  | 2,418 | 2,171
Average Recorded Investment, With no related allowance recorded |  | 2,099 | 1,474
Average Recorded Investment, With an allowance recorded |  | 5,957 | 5,984
Average Recorded Investment |  | 8,056 | 7,458
Interest Income Recognized, With no related allowance recorded |  |  |
Interest Income Recognized, With an allowance recorded |  |  |
Interest Income Recognized |  |  |
Commercial Business [Member] |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Recorded Investment, With no related allowance recorded | [1] | 1,259 | 1,635
Recorded Investment, With an allowance recorded | [1] | 3,194 | 3,853
Unpaid Principal Balance, With no related allowance recorded | [1] | 1,775 | 2,370
Unpaid Principal Balance, With an allowance recorded | [1] | 3,286 | 3,853
Related Allowance |  | 1,699 | 2,056
Average Recorded Investment, With no related allowance recorded |  | 1,523 | 853
Average Recorded Investment, With an allowance recorded |  | 3,587 | 4,468
Interest Income Recognized, With no related allowance recorded |  |  |
Interest Income Recognized, With an allowance recorded |  |  |
Commercial Mortgage [Member] |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Recorded Investment, With no related allowance recorded | [1] | 569 | 584
Recorded Investment, With an allowance recorded | [1] | 2,222 | 2,528
Unpaid Principal Balance, With no related allowance recorded | [1] | 569 | 584
Unpaid Principal Balance, With an allowance recorded | [1] | 2,222 | 2,528
Related Allowance |  | 719 | 115
Average Recorded Investment, With no related allowance recorded |  | 576 | 621
Average Recorded Investment, With an allowance recorded |  | 2,370 | 1,516
Interest Income Recognized, With no related allowance recorded |  |  |
Interest Income Recognized, With an allowance recorded |  |  |
[1] | Difference between recorded investment and unpaid principal balance represents partial charge-offs.

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