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, 2017	Dec. 31, 2016	Mar. 31, 2017	Dec. 31, 2016
Allowance for credit losses:
Beginning balance	$ 20,912	$ 16,316
Charge-offs	(209)	(3,594)
Recoveries	391	372
Provision	572	7,818
Ending balance	20,912	16,316	$ 21,666	$ 20,912
Ending balance: individually evaluated for impairment			6,158	5,599
Ending balance: collectively evaluated for impairment			15,508	15,313
Loans and lease receivables:
Total gross loans and leases receivable			1,482,297	1,451,864
Ending balance: individually evaluated for impairment			36,940	24,286
Ending balance: collectively evaluated for impairment			$ 1,444,076	$ 1,425,953
Allowance as % of gross loans and leases			1.46%	1.44%
Commercial real estate:
Allowance for credit losses:
Beginning balance	12,384	11,220
Charge-offs	(67)	(1,194)
Recoveries	104	274
Provision	396	2,084
Ending balance	12,384	11,220	$ 12,817	$ 12,384
Ending balance: individually evaluated for impairment			1,821	1,899
Ending balance: collectively evaluated for impairment			10,996	10,485
Loans and lease receivables:
Total gross loans and leases receivable			967,093	945,874
Ending balance: individually evaluated for impairment			16,693	11,222
Ending balance: collectively evaluated for impairment			$ 949,128	$ 933,048
Allowance as % of gross loans and leases			1.33%	1.31%
Commercial and industrial loans and leases
Allowance for credit losses:
Beginning balance	7,970	4,387
Charge-offs	(55)	(2,273)
Recoveries	246	91
Provision	(218)	5,765
Ending balance	7,970	4,387	$ 7,943	$ 7,970
Ending balance: individually evaluated for impairment			4,010	3,700
Ending balance: collectively evaluated for impairment			3,933	4,270
Loans and lease receivables:
Total gross loans and leases receivable			488,108	481,249
Ending balance: individually evaluated for impairment			19,545	12,452
Ending balance: collectively evaluated for impairment			$ 468,554	$ 468,776
Allowance as % of gross loans and leases			1.63%	1.66%
Consumer and other:
Allowance for credit losses:
Beginning balance	558	709
Charge-offs	(87)	(127)
Recoveries	41	7
Provision	394	(31)
Ending balance	$ 558	$ 709	$ 906	$ 558
Ending balance: individually evaluated for impairment			327	0
Ending balance: collectively evaluated for impairment			579	558
Loans and lease receivables:
Total gross loans and leases receivable			27,096	24,741
Ending balance: individually evaluated for impairment			702	612
Ending balance: collectively evaluated for impairment			$ 26,394	$ 24,129
Allowance as % of gross loans and leases			3.34%	2.26%
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			1,281	1,625
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			1,272	1,604
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			9	21
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			$ 0	$ 0

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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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 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=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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