LOANS, Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Allowance for loan losses [Roll Forward]
Beginning balance	$ 47,233	$ 45,401
Charge-offs	(3,182)	(2,671)
Recoveries	1,217	1,525
Provision	1,828	1,341
Ending balance	47,096	45,596
Acquired Impaired [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	108	168
Charge-offs	0	0
Recoveries	0	0
Provision	2	(83)
Ending balance	110	85
Residential Portfolio Segment [Member] \| Consumer Mortgage [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	10,094	10,198
Charge-offs	(85)	(88)
Recoveries	7	45
Provision	133	(7)
Ending balance	10,149	10,148
Commercial Portfolio Segment [Member] \| Business Lending [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	17,220	15,749
Charge-offs	(695)	(210)
Recoveries	71	136
Provision	261	1,020
Ending balance	16,857	16,695
Consumer Portfolio Segment [Member] \| Consumer Indirect [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	13,782	12,422
Charge-offs	(1,947)	(1,854)
Recoveries	869	1,114
Provision	1,292	652
Ending balance	13,996	12,334
Consumer Portfolio Segment [Member] \| Consumer Direct [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	2,979	2,997
Charge-offs	(417)	(462)
Recoveries	245	221
Provision	45	119
Ending balance	2,852	2,875
Consumer Portfolio Segment [Member] \| Home Equity [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	2,399	2,666
Charge-offs	(38)	(57)
Recoveries	25	9
Provision	(27)	(38)
Ending balance	2,359	2,580
Unallocated Financing Receivables [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	651	1,201
Charge-offs	0	0
Recoveries	0	0
Provision	122	(322)
Ending balance	$ 773	$ 879

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
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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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