Allowance for Loan Losses (Allowance for Loan Losses Rollforward Analysis) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance, Beginning Balance	$ 28,023	$ 27,886
Charge-offs	(321)	(1,223)
Recoveries	108	80
Provision	0	300
Allowance, Ending Balance	27,810	27,043
Reclassification of unallocated allowance [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance, Ending Balance	5,300
Commercial Mortgages [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance, Beginning Balance	8,202	8,022
Charge-offs	(200)	(945)
Recoveries	80	6
Provision	249	(536)
Allowance, Ending Balance	8,331	6,547
Commercial Construction & Development [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance, Beginning Balance	1,300	383
Charge-offs	0	0
Recoveries	0	0
Provision	(71)	(114)
Allowance, Ending Balance	1,229	269
Commercial & Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance, Beginning Balance	7,987	7,835
Charge-offs	(7)	(196)
Recoveries	14	26
Provision	(191)	805
Allowance, Ending Balance	7,803	8,470
Commercial Segment [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance, Beginning Balance	17,489	16,240
Charge-offs	(207)	(1,141)
Recoveries	94	32
Provision	(13)	155
Allowance, Ending Balance	17,363	15,286
Residential Segment [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance, Beginning Balance	5,430	6,450
Charge-offs	(48)	(42)
Recoveries	2	35
Provision	(29)	705
Allowance, Ending Balance	5,355	7,148
Consumer Segment [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance, Beginning Balance	2,713	2,511
Charge-offs	(66)	(40)
Recoveries	12	13
Provision	72	93
Allowance, Ending Balance	2,731	2,577
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance, Beginning Balance	2,391	2,685
Charge-offs	0	0
Recoveries	0	0
Provision	(30)	(653)
Allowance, Ending Balance	$ 2,361	$ 2,032

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

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)(4)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

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

+ 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)(3)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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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 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

-Paragraph 11B

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-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

Reference 4: http://www.xbrl.org/2003/role/presentationRef

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-Section 50

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-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Section 50

-Paragraph 2

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-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

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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 230

-SubTopic 10

-Section 45

-Paragraph 28

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-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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