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Bank Loans (Loans That Were Individually Evaluated For Impairment By Portfolio Segment) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016
Financing Receivable Impaired [Line Items] |  |
Unpaid Contractual Principal Balance | $ 29,888 | $ 28,742
Recorded Investment with No Allowance | 5,211 |
Recorded Investment with Allowance | 24,002 | 26,934
Total Recorded Investment | 29,213 | 26,934
Related Allowance | 9,105 | 3,375
Average Recorded Investment | 30,756 | 32,242
Commercial And Industrial [Member] |  |
Financing Receivable Impaired [Line Items] |  |
Unpaid Contractual Principal Balance | 28,856 | 16,815
Recorded Investment with No Allowance | 5,211 |
Recorded Investment with Allowance | 23,645 | 16,815
Total Recorded Investment | 28,856 | 16,815
Related Allowance | 9,059 | 2,392
Average Recorded Investment | 30,277 | 22,559
Consumer [Member] |  |
Financing Receivable Impaired [Line Items] |  |
Unpaid Contractual Principal Balance | 677 | 833
Recorded Investment with Allowance | 2 | 6
Total Recorded Investment | 2 | 6
Related Allowance | 2 | 6
Average Recorded Investment | 5 | 9
Residential Real Estate [Member] |  |
Financing Receivable Impaired [Line Items] |  |
Unpaid Contractual Principal Balance | 171 | 178
Recorded Investment with Allowance | 171 | 178
Total Recorded Investment | 171 | 178
Related Allowance | 24 | 24
Average Recorded Investment | 174 | 181
Home Equity Lines Of Credit [Member] |  |
Financing Receivable Impaired [Line Items] |  |
Unpaid Contractual Principal Balance | 184 | 413
Recorded Investment with Allowance | 184 | 413
Total Recorded Investment | 184 | 413
Related Allowance | 20 | 231
Average Recorded Investment | $ 300 | 413
Commercial Real Estate [Member] |  |
Financing Receivable Impaired [Line Items] |  |
Unpaid Contractual Principal Balance |  | 10,503
Recorded Investment with Allowance |  | 9,522
Total Recorded Investment |  | 9,522
Related Allowance |  | 722
Average Recorded Investment |  | $ 9,080

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