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	9 Months Ended	12 Months Ended
Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2016	Dec. 31, 2015
Allowance for credit losses:
Beginning balance	$ 16,316	$ 14,329
Charge-offs	(3,250)	(1,513)
Recoveries	177	114
Provision	6,824	3,386
Ending balance	16,316	14,329	$ 20,067	$ 16,316
Ending balance: individually evaluated for impairment			4,636	1,113
Ending balance: collectively evaluated for impairment			15,431	15,203
Loans and lease receivables:
Total gross loans and leases receivable			1,459,464	1,432,027
Ending balance: individually evaluated for impairment			24,312	20,852
Ending balance: collectively evaluated for impairment			$ 1,433,020	$ 1,408,187
Allowance as % of gross loans and leases			1.37%	1.14%
Commercial real estate
Allowance for credit losses:
Beginning balance	11,220	8,619
Charge-offs	(1,194)	(793)
Recoveries	170	104
Provision	2,619	3,290
Ending balance	11,220	8,619	$ 12,815	$ 11,220
Ending balance: individually evaluated for impairment			1,385	240
Ending balance: collectively evaluated for impairment			11,430	10,980
Loans and lease receivables:
Total gross loans and leases receivable			942,906	904,185
Ending balance: individually evaluated for impairment			13,953	10,849
Ending balance: collectively evaluated for impairment			$ 927,017	$ 890,594
Allowance as % of gross loans and leases			1.36%	1.24%
Commercial and industrial loans and leases
Allowance for credit losses:
Beginning balance	4,387	5,492
Charge-offs	(2,048)	(711)
Recoveries	2	6
Provision	4,331	(400)
Ending balance	4,387	5,492	$ 6,672	$ 4,387
Ending balance: individually evaluated for impairment			3,251	847
Ending balance: collectively evaluated for impairment			3,421	3,540
Loans and lease receivables:
Total gross loans and leases receivable			494,558	503,286
Ending balance: individually evaluated for impairment			9,946	8,942
Ending balance: collectively evaluated for impairment			$ 484,589	$ 494,098
Allowance as % of gross loans and leases			1.35%	0.87%
Consumer and other
Allowance for credit losses:
Beginning balance	709	218
Charge-offs	(8)	(9)
Recoveries	5	4
Provision	(126)	496
Ending balance	$ 709	$ 218	$ 580	$ 709
Ending balance: individually evaluated for impairment			0	26
Ending balance: collectively evaluated for impairment			580	683
Loans and lease receivables:
Total gross loans and leases receivable			22,000	24,556
Ending balance: individually evaluated for impairment			413	1,061
Ending balance: collectively evaluated for impairment			$ 21,414	$ 23,495
Allowance as % of gross loans and leases			2.64%	2.89%
Ending balance: loans acquired with deteriorated credit quality
Allowance for credit losses:
Ending balance: individually evaluated for impairment			$ 0	$ 0
Loans and lease receivables:
Ending balance: individually evaluated for impairment			2,132	3,181
Ending balance: loans acquired with deteriorated credit quality \| Commercial real estate
Allowance for credit losses:
Ending balance: individually evaluated for impairment			0	0
Loans and lease receivables:
Ending balance: individually evaluated for impairment			1,936	2,742
Ending balance: loans acquired with deteriorated credit quality \| Commercial and industrial loans and leases
Allowance for credit losses:
Ending balance: individually evaluated for impairment			0	0
Loans and lease receivables:
Ending balance: individually evaluated for impairment			23	246
Ending balance: loans acquired with deteriorated credit quality \| Consumer and other
Allowance for credit losses:
Ending balance: individually evaluated for impairment			0	0
Loans and lease receivables:
Ending balance: individually evaluated for impairment			$ 173	$ 193

Ratio of Allowance for Loan and Lease Losses to Total Gross Loans and Leases

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

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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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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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Amount of direct write-downs of financing receivables charged against the allowance.

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The balance of financing receivables that were collectively evaluated for impairment.

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes 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 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ 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 (c)(2)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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