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Summary Of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015
Significant Accounting Policies [Line Items] |  |
Days past due when loans are generally placed on nonaccrual status, in days | 90 days | 90 days
Days past due when loans are generally charged-off in full, in days | 120 days |
General period after loans become current, accrual status returned, in months | 6 months |
Other real estate owned | $ 107 | $ 163
Number of consecutive years used for compensation calculation | 5 years |
FHLB stock | $ 16,900 | 15,100
FRB stock | 4,900 | 4,900
Equity method investments, asset amount | $ 5,600 | $ 5,000
Minimum [Member] |  |
Significant Accounting Policies [Line Items] |  |
Standby letters of credit outstanding original term, in years | 1 year |
Loss rate look-back period | 24 months |
Loss emergence period | 12 months |
Minimum [Member] | Building And Building Improvements [Member] |  |
Significant Accounting Policies [Line Items] |  |
Premise and equipment, estimated useful lives, in years | 15 years |
Minimum [Member] | Software Furniture And Equipment [Member] |  |
Significant Accounting Policies [Line Items] |  |
Premise and equipment, estimated useful lives, in years | 3 years |
Maximum [Member] |  |
Significant Accounting Policies [Line Items] |  |
Standby letters of credit outstanding original term, in years | 5 years |
Loss emergence period | 28 months |
Maximum [Member] | Building And Building Improvements [Member] |  |
Significant Accounting Policies [Line Items] |  |
Premise and equipment, estimated useful lives, in years | 39 years |
Maximum [Member] | Software Furniture And Equipment [Member] |  |
Significant Accounting Policies [Line Items] |  |
Premise and equipment, estimated useful lives, in years | 10 years |
Other Intangible Assets [Member] |  |
Significant Accounting Policies [Line Items] |  |
Estimated average life | 20 years |
Core Deposits [Member] |  |
Significant Accounting Policies [Line Items] |  |
Estimated average life | 9 years 6 months |

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