LOANS, Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Allowance for loan losses [Roll Forward]
Beginning balance	$ 48,103	$ 47,096	$ 47,583	$ 47,233
Charge-offs	(2,622)	(3,041)	(7,369)	(6,223)
Recoveries	1,689	1,935	3,277	3,152
Provision	2,448	1,461	6,127	3,289
Ending balance	49,618	47,451	49,618	47,451
Acquired Impaired [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	308	110	147	108
Charge-offs	(323)	(183)	(367)	(184)
Recoveries	0	0	0	0
Provision	48	136	253	139
Ending balance	33	63	33	63
Residential Portfolio Segment [Member] \| Business Lending [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	17,607	16,857
Charge-offs	(260)	(245)
Recoveries	114	283
Provision	978	335
Ending balance	18,439	17,230	18,439	17,230
Residential Portfolio Segment [Member] \| Consumer Mortgage [Member]
Allowance for loan losses [Roll Forward]
Beginning balance			17,257	17,220
Charge-offs			(1,928)	(938)
Recoveries			312	354
Provision			2,798	594
Ending balance	18,439	17,230	18,439	17,230
Commercial Portfolio Segment [Member] \| Business Lending [Member]
Allowance for loan losses [Roll Forward]
Beginning balance			10,465	10,094
Charge-offs			(444)	(343)
Recoveries			62	18
Provision			390	428
Ending balance	10,473	10,197	10,473	10,197
Commercial Portfolio Segment [Member] \| Consumer Mortgage [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	10,382	10,149
Charge-offs	(245)	(258)
Recoveries	54	11
Provision	282	295
Ending balance	10,473	10,197	10,473	10,197
Consumer Portfolio Segment [Member] \| Consumer Indirect [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	13,698	13,996	13,468	13,782
Charge-offs	(1,383)	(1,695)	(3,667)	(3,642)
Recoveries	1,347	1,452	2,498	2,321
Provision	762	165	2,125	1,457
Ending balance	14,424	13,918	14,424	13,918
Consumer Portfolio Segment [Member] \| Consumer Direct [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	2,984	2,852	3,039	2,979
Charge-offs	(364)	(470)	(860)	(888)
Recoveries	167	182	389	427
Provision	377	381	596	427
Ending balance	3,164	2,945	3,164	2,945
Consumer Portfolio Segment [Member] \| Home Equity [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	2,040	2,359	2,107	2,399
Charge-offs	(47)	(190)	(103)	(228)
Recoveries	7	7	16	32
Provision	15	66	(5)	39
Ending balance	2,015	2,242	2,015	2,242
Unallocated Financing Receivables [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	1,084	773	1,100	651
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(14)	83	(30)	205
Ending balance	$ 1,070	$ 856	$ 1,070	$ 856

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

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- Definition

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

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