Loan and Lease Receivables, Impaired Loans and Leases and Allowance for Loan and Lease Losses (Allowance for Loan and Lease Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Allowance for credit losses roll-forward
Allowance for loan and lease losses - begin	$ 20,932	$ 21,677	$ 18,763	$ 20,912
Charge-offs	(1,914)	(3,230)	(4,904)	(7,196)
Recoveries	1,983	5	2,088	508
Net (charge-offs) recoveries	69	(3,225)	(2,816)	(6,688)
Provision for credit loss	(546)	1,471	4,508	5,699
Allowance for loan and lease losses - end	20,455	19,923	20,455	19,923
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	15,886		15,886		$ 14,272
Commercial real estate:
Allowance for credit losses roll-forward
Allowance for loan and lease losses - begin	11,147	12,003	10,131	12,384
Charge-offs	(1,826)	(8)	(4,122)	(126)
Recoveries	7	2	22	152
Net (charge-offs) recoveries	(1,819)	(6)	(4,100)	26
Provision for credit loss	2,365	(2,462)	5,662	(2,875)
Allowance for loan and lease losses - end	11,693	9,535	11,693	9,535
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	11,086		11,086		9,716
Commercial and industrial loans and leases
Allowance for credit losses roll-forward
Allowance for loan and lease losses - begin	9,237	9,090	8,225	7,970
Charge-offs	(75)	(3,217)	(732)	(6,978)
Recoveries	1,974	2	1,993	314
Net (charge-offs) recoveries	1,899	(3,215)	1,261	(6,664)
Provision for credit loss	(3,252)	3,968	(1,602)	8,537
Allowance for loan and lease losses - end	7,884	9,843	7,884	9,843
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	4,082		4,082		4,158
Consumer and other:
Allowance for credit losses roll-forward
Allowance for loan and lease losses - begin	548	584	407	558
Charge-offs	(13)	(5)	(50)	(92)
Recoveries	2	1	73	42
Net (charge-offs) recoveries	(11)	(4)	23	(50)
Provision for credit loss	341	(35)	448	37
Allowance for loan and lease losses - end	878	$ 545	878	$ 545
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	$ 718		$ 718		$ 398

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.

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

+ References

No definition available.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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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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