LOANS, Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Allowance for loan losses [Roll Forward]
Beginning balance	$ 47,096	$ 45,596	$ 47,233	$ 45,401
Charge-offs	(3,041)	(2,966)	(6,223)	(5,638)
Recoveries	1,935	1,591	3,152	3,117
Provision	1,461	2,305	3,289	3,646
Ending balance	47,451	46,526	47,451	46,526
Acquired Impaired [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	110	85	108	168
Charge-offs	(183)	(26)	(184)	(26)
Recoveries	0	0	0	0
Provision	136	80	139	(3)
Ending balance	63	139	63	139
Residential Portfolio Segment [Member] \| Consumer Mortgage [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	10,149	10,148	10,094	10,198
Charge-offs	(258)	(156)	(343)	(243)
Recoveries	11	38	18	83
Provision	295	(177)	428	(185)
Ending balance	10,197	9,853	10,197	9,853
Commercial Portfolio Segment [Member] \| Business Lending [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	16,857	16,695	17,220	15,749
Charge-offs	(245)	(770)	(938)	(979)
Recoveries	283	156	354	291
Provision	335	868	594	1,888
Ending balance	17,230	16,949	17,230	16,949
Consumer Portfolio Segment [Member] \| Consumer Indirect [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	13,996	12,334	13,782	12,422
Charge-offs	(1,695)	(1,545)	(3,642)	(3,401)
Recoveries	1,452	1,140	2,321	2,255
Provision	165	1,286	1,457	1,939
Ending balance	13,918	13,215	13,918	13,215
Consumer Portfolio Segment [Member] \| Consumer Direct [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	2,852	2,875	2,979	2,997
Charge-offs	(470)	(389)	(888)	(852)
Recoveries	182	238	427	460
Provision	381	296	427	415
Ending balance	2,945	3,020	2,945	3,020
Consumer Portfolio Segment [Member] \| Home Equity [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	2,359	2,580	2,399	2,666
Charge-offs	(190)	(80)	(228)	(137)
Recoveries	7	19	32	28
Provision	66	(19)	39	(57)
Ending balance	2,242	2,500	2,242	2,500
Unallocated Financing Receivables [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	773	879	651	1,201
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	83	(29)	205	(351)
Ending balance	$ 856	$ 850	$ 856	$ 850

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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- 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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-Publisher FASB
-Name Accounting Standards Codification
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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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