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Bank Loans (Loans That Were Individually Evaluated For Impairment By Portfolio Segment) (Details) - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2018 | Dec. 31, 2017
Financing Receivable Impaired [Line Items] |  |
Unpaid Contractual Principal Balance | $ 24,747 | $ 29,888
Recorded Investment with No Allowance | 9 | 5,211
Recorded Investment with Allowance | 24,075 | 24,002
Total Recorded Investment | 24,084 | 29,213
Related Allowance | 9,156 | 9,105
Average Recorded Investment | 24,028 | 30,756
Commercial And Industrial [Member] |  |
Financing Receivable Impaired [Line Items] |  |
Unpaid Contractual Principal Balance | 23,719 | 28,856
Recorded Investment with No Allowance |  | 5,211
Recorded Investment with Allowance | 23,720 | 23,645
Total Recorded Investment | 23,720 | 28,856
Related Allowance | 9,111 | 9,059
Average Recorded Investment | 23,663 | 30,277
Consumer [Member] |  |
Financing Receivable Impaired [Line Items] |  |
Unpaid Contractual Principal Balance | 674 | 677
Recorded Investment with Allowance | 1 | 2
Total Recorded Investment | 1 | 2
Related Allowance | 1 | 2
Average Recorded Investment | 2 | 5
Residential Real Estate [Member] |  |
Financing Receivable Impaired [Line Items] |  |
Unpaid Contractual Principal Balance | 170 | 171
Recorded Investment with Allowance | 170 | 171
Total Recorded Investment | 170 | 171
Related Allowance | 24 | 24
Average Recorded Investment | 170 | 174
Home Equity Lines Of Credit [Member] |  |
Financing Receivable Impaired [Line Items] |  |
Unpaid Contractual Principal Balance | 184 | 184
Recorded Investment with No Allowance | 9 |
Recorded Investment with Allowance | 184 | 184
Total Recorded Investment | 193 | 184
Related Allowance | 20 | 20
Average Recorded Investment | $ 193 | $ 300

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