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
Mar. 31, 2018	Mar. 31, 2017
Allowance for credit losses roll-forward
Allowance for loan and lease losses - begin	$ 18,763
Charge-offs	(2,685)	$ (209)
Recoveries	84	391
Net (charge-offs) recoveries	(2,601)	182
Provision for credit loss	2,476	572
Allowance for loan and lease losses - end	18,638
Commercial real estate:
Allowance for credit losses roll-forward
Allowance for loan and lease losses - begin	10,131
Charge-offs	(2,175)	(67)
Recoveries	13	104
Net (charge-offs) recoveries	(2,162)	37
Provision for credit loss	2,021	396
Allowance for loan and lease losses - end	9,990
Commercial and industrial loans and leases
Allowance for credit losses roll-forward
Allowance for loan and lease losses - begin	8,225
Charge-offs	(490)	(55)
Recoveries	2	246
Net (charge-offs) recoveries	(488)	191
Provision for credit loss	414	(218)
Allowance for loan and lease losses - end	8,151
Consumer and other:
Allowance for credit losses roll-forward
Allowance for loan and lease losses - begin	407
Charge-offs	(20)	(87)
Recoveries	69	41
Net (charge-offs) recoveries	49	(46)
Provision for credit loss	41	$ 394
Allowance for loan and lease losses - end	$ 497

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.

+ References

No definition available.

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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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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
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