LOANS, Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Allowance for loan losses [Roll Forward]
Beginning balance	$ 47,583	$ 47,233
Charge-offs	(4,747)	(3,182)
Recoveries	1,588	1,217
Provision	3,679	1,828
Ending balance	48,103	47,096
Acquired Impaired [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	147	108
Charge-offs	(43)	0
Recoveries	0	0
Provision	204	2
Ending balance	308	110
Residential Portfolio Segment [Member] \| Business Lending [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	17,257	17,220
Charge-offs	(1,669)	(695)
Recoveries	198	71
Provision	1,821	261
Ending balance	17,607	16,857
Commercial Portfolio Segment [Member] \| Consumer Mortgage [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	10,465	10,094
Charge-offs	(199)	(85)
Recoveries	8	7
Provision	108	133
Ending balance	10,382	10,149
Consumer Portfolio Segment [Member] \| Consumer Indirect [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	13,468	13,782
Charge-offs	(2,284)	(1,947)
Recoveries	1,151	869
Provision	1,363	1,292
Ending balance	13,698	13,996
Consumer Portfolio Segment [Member] \| Consumer Direct [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	3,039	2,979
Charge-offs	(496)	(417)
Recoveries	222	245
Provision	219	45
Ending balance	2,984	2,852
Consumer Portfolio Segment [Member] \| Home Equity [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	2,107	2,399
Charge-offs	(56)	(38)
Recoveries	9	25
Provision	(20)	(27)
Ending balance	2,040	2,359
Unallocated Financing Receivables [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	1,100	651
Charge-offs	0	0
Recoveries	0	0
Provision	(16)	122
Ending balance	$ 1,084	$ 773

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

No definition available.

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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
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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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