LOANS, Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Allowance for loan losses [Roll Forward]
Beginning balance	$ 46,526	$ 45,282	$ 45,401	$ 45,341
Charge-offs	(2,924)	(2,659)	(8,561)	(7,361)
Recoveries	1,397	1,059	4,513	4,488
Provision	1,790	1,906	5,436	3,120
Ending balance	46,789	45,588	46,789	45,588
Acquired Impaired [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	139	93	168	173
Charge-offs	0	(59)	(26)	(102)
Recoveries	0	0	0	0
Provision	0	6	(3)	(31)
Ending balance	139	40	139	40
Residential Portfolio Segment [Member] \| Consumer Mortgage [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	9,853	10,192	10,198	10,286
Charge-offs	(202)	(276)	(445)	(917)
Recoveries	12	9	96	75
Provision	305	421	119	902
Ending balance	9,968	10,346	9,968	10,346
Commercial Portfolio Segment [Member] \| Business Lending [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	16,949	15,353	15,749	15,787
Charge-offs	(284)	(234)	(1,263)	(667)
Recoveries	220	107	511	715
Provision	(283)	112	1,605	(497)
Ending balance	16,602	15,338	16,602	15,338
Consumer Portfolio Segment [Member] \| Consumer Indirect [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	13,215	11,602	12,422	11,544
Charge-offs	(2,037)	(1,597)	(5,439)	(4,421)
Recoveries	892	740	3,146	3,077
Provision	1,503	1,367	3,444	1,912
Ending balance	13,573	12,112	13,573	12,112
Consumer Portfolio Segment [Member] \| Consumer Direct [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	3,020	2,991	2,997	3,083
Charge-offs	(395)	(427)	(1,246)	(1,066)
Recoveries	246	174	705	566
Provision	170	359	585	514
Ending balance	3,041	3,097	3,041	3,097
Consumer Portfolio Segment [Member] \| Home Equity [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	2,500	2,677	2,666	2,701
Charge-offs	(6)	(66)	(142)	(188)
Recoveries	27	29	55	55
Provision	10	102	(48)	174
Ending balance	2,531	2,742	2,531	2,742
Unallocated Financing Receivables [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	850	2,374	1,201	1,767
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	85	(461)	(266)	146
Ending balance	$ 935	$ 1,913	$ 935	$ 1,913

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.

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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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-Publisher FASB
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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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