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	12 Months Ended
Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2016	Dec. 31, 2015
Allowance for credit losses:
Beginning balance	$ 16,316	$ 14,329
Charge-offs	(244)	(1,513)
Recoveries	87	114
Provision	525	3,386
Ending balance	16,316	14,329	$ 16,684	$ 16,316
Ending balance: individually evaluated for impairment			897	1,113
Ending balance: collectively evaluated for impairment			15,787	15,203
Loans and lease receivables:
Total gross loans and leases receivable			1,451,293	1,434,729
Ending balance: individually evaluated for impairment			16,380	20,852
Ending balance: collectively evaluated for impairment			$ 1,431,803	$ 1,410,889
Allowance as % of gross loans			1.15%	1.14%
Commercial real estate
Allowance for credit losses:
Beginning balance	11,220	8,619
Charge-offs	(41)	(793)
Recoveries	84	104
Provision	217	3,290
Ending balance	11,220	8,619	$ 11,480	$ 11,220
Ending balance: individually evaluated for impairment			144	240
Ending balance: collectively evaluated for impairment			11,336	10,980
Loans and lease receivables:
Total gross loans and leases receivable			932,227	905,488
Ending balance: individually evaluated for impairment			9,106	10,849
Ending balance: collectively evaluated for impairment			$ 920,443	$ 891,897
Allowance as % of gross loans			1.23%	1.24%
Commercial and industrial loans and leases
Allowance for credit losses:
Beginning balance	4,387	5,492
Charge-offs	(196)	(711)
Recoveries	0	6
Provision	297	(400)
Ending balance	4,387	5,492	$ 4,488	$ 4,387
Ending balance: individually evaluated for impairment			730	847
Ending balance: collectively evaluated for impairment			3,758	3,540
Loans and lease receivables:
Total gross loans and leases receivable			493,190	504,685
Ending balance: individually evaluated for impairment			6,481	8,942
Ending balance: collectively evaluated for impairment			$ 486,468	$ 495,497
Allowance as % of gross loans			0.91%	0.87%
Consumer and other
Allowance for credit losses:
Beginning balance	709	218
Charge-offs	(7)	(9)
Recoveries	3	4
Provision	11	496
Ending balance	$ 709	$ 218	$ 716	$ 709
Ending balance: individually evaluated for impairment			23	26
Ending balance: collectively evaluated for impairment			693	683
Loans and lease receivables:
Total gross loans and leases receivable			25,876	24,556
Ending balance: individually evaluated for impairment			793	1,061
Ending balance: collectively evaluated for impairment			$ 24,892	$ 23,495
Allowance as % of gross loans			2.77%	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			3,110	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			2,678	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			241	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			$ 191	$ 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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- 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=28367877&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=49124121&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=56944662&loc=d3e3602-108585

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