LOANS, Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Allowance for loan losses [Roll Forward]
Beginning balance	$ 45,282	$ 44,615	$ 45,341	$ 44,319
Charge-offs	(2,659)	(2,740)	(7,361)	(7,946)
Recoveries	1,059	1,651	4,488	4,253
Provision	1,906	1,747	3,120	4,647
Ending balance	45,588	45,273	45,588	45,273
Acquired Impaired [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	93	163	173	530
Charge-offs	(59)	(10)	(102)	(30)
Recoveries	0	0	0	0
Provision	6	(2)	(31)	(349)
Ending balance	40	151	40	151
Residential Portfolio Segment [Member] \| Consumer Mortgage [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	10,192	9,375	10,286	8,994
Charge-offs	(276)	(203)	(917)	(734)
Recoveries	9	14	75	67
Provision	421	268	902	1,127
Ending balance	10,346	9,454	10,346	9,454
Commercial Portfolio Segment [Member] \| Business Lending [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	15,353	16,553	15,787	17,507
Charge-offs	(234)	(435)	(667)	(940)
Recoveries	107	335	715	607
Provision	112	138	(497)	(583)
Ending balance	15,338	16,591	15,338	16,591
Consumer Portfolio Segment [Member] \| Consumer Indirect [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	11,602	11,354	11,544	10,248
Charge-offs	(1,597)	(1,711)	(4,421)	(4,573)
Recoveries	740	1,025	3,077	2,826
Provision	1,367	1,231	1,912	3,398
Ending balance	12,112	11,899	12,112	11,899
Consumer Portfolio Segment [Member] \| Consumer Direct [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	2,991	3,298	3,083	3,181
Charge-offs	(427)	(307)	(1,066)	(1,219)
Recoveries	174	239	566	677
Provision	359	100	514	691
Ending balance	3,097	3,330	3,097	3,330
Consumer Portfolio Segment [Member] \| Home Equity [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	2,677	1,860	2,701	1,830
Charge-offs	(66)	(74)	(188)	(450)
Recoveries	29	38	55	76
Provision	102	77	174	445
Ending balance	2,742	1,901	2,742	1,901
Unallocated Financing Receivables [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	2,374	2,012	1,767	2,029
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(461)	(65)	146	(82)
Ending balance	$ 1,913	$ 1,947	$ 1,913	$ 1,947

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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- Definition

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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- 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)

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-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

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