Loan and Lease Receivables, Impaired Loans and Leases and Allowance for Loan and Lease Losses (Summary of Activity in Allowance for Loan and Lease Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Allowance for credit losses roll-forward
Allowance for loan and lease losses - begin	$ 19,819	$ 20,932	$ 20,425	$ 18,763
Charge-offs	(1,099)	(1,914)	(1,162)	(4,904)
Recoveries	101	1,983	294	2,088
Net (charge-offs) recoveries	(998)	69	(868)	(2,816)
Provision for credit loss	1,349	(546)	613	4,508
Allowance for loan and lease losses - end	20,170	20,455	20,170	20,455
Total commercial real estate
Allowance for credit losses roll-forward
Allowance for loan and lease losses - begin	11,269	11,147	11,662	10,131
Charge-offs	0	(1,826)	0	(4,122)
Recoveries	1	7	74	22
Net (charge-offs) recoveries	1	(1,819)	74	(4,100)
Provision for credit loss	(132)	2,365	(598)	5,662
Allowance for loan and lease losses - end	11,138	11,693	11,138	11,693
Total commercial and Industrial
Allowance for credit losses roll-forward
Allowance for loan and lease losses - begin	7,892	9,237	8,079	8,225
Charge-offs	(1,097)	(75)	(1,158)	(732)
Recoveries	99	1,974	191	1,993
Net (charge-offs) recoveries	(998)	1,899	(967)	1,261
Provision for credit loss	1,517	(3,252)	1,299	(1,602)
Allowance for loan and lease losses - end	8,411	7,884	8,411	7,884
Total consumer and other
Allowance for credit losses roll-forward
Allowance for loan and lease losses - begin	658	548	684	407
Charge-offs	(2)	(13)	(4)	(50)
Recoveries	1	2	29	73
Net (charge-offs) recoveries	(1)	(11)	25	23
Provision for credit loss	(36)	341	(88)	448
Allowance for loan and lease losses - end	$ 621	$ 878	$ 621	$ 878

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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Amount, after recoveries, of loans and leases that have been written-off.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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