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Loan and Lease Receivables, Impaired Loans and Leases and Allowance for Loan and Lease Losses (Troubled Debt Restructurings) (Details) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2018 loans | Sep. 30, 2017 loans | Dec. 31, 2017 USD ($)
Troubled debt restructurings |  |  |
Number of loans | loans | 0 | 5 |
Pre-Modification Recorded Investment |  |  | $ 4,391
Post-Modification Recorded Investment |  |  | 4,417
Commercial and industrial |  |  |
Troubled debt restructurings |  |  |
Number of loans | loans |  | 4 |
Pre-Modification Recorded Investment |  |  | 4,374
Post-Modification Recorded Investment |  |  | 4,400
Other |  |  |
Troubled debt restructurings |  |  |
Number of loans | loans |  | 1 |
Pre-Modification Recorded Investment |  |  | 17
Post-Modification Recorded Investment |  |  | $ 17

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