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Bank Loans (Loans That Were Individually Evaluated For Impairment By Portfolio Segment) (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2020 | Dec. 31, 2019
Financing Receivable Impaired [Line Items] |  |
Unpaid Contractual Principal Balance | $ 14,643 | $ 14,737
Recorded Investment with No Allowance | 1,249 | 1,647
Recorded Investment with Allowance | 13,244 | 12,940
Total Recorded Investment | 14,493 | 14,587
Related Allowance | 8,182 | 8,182
Average Recorded Investment | 14,645 | 15,587
Commercial And Industrial [Member] |  |
Financing Receivable Impaired [Line Items] |  |
Unpaid Contractual Principal Balance | 13,084 | 12,991
Recorded Investment with No Allowance |  | 51
Recorded Investment with Allowance | 13,084 | 12,940
Total Recorded Investment | 13,084 | 12,991
Related Allowance | 8,158 | 8,158
Average Recorded Investment | 13,085 | 14,172
Residential Real Estate [Member] |  |
Financing Receivable Impaired [Line Items] |  |
Unpaid Contractual Principal Balance | 1,409 | 1,412
Recorded Investment with No Allowance | 1,249 | 1,412
Recorded Investment with Allowance | 160 |
Total Recorded Investment | 1,409 | 1,412
Related Allowance | 24 | 24
Average Recorded Investment | 1,499 | 1,231
Home Equity Lines Of Credit [Member] |  |
Financing Receivable Impaired [Line Items] |  |
Unpaid Contractual Principal Balance |  | 184
Recorded Investment with No Allowance |  | 184
Total Recorded Investment |  | 184
Average Recorded Investment | 61 | 184
Other [Member] |  |
Financing Receivable Impaired [Line Items] |  |
Unpaid Contractual Principal Balance | $ 150 | $ 150

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