ALLOWANCE FOR CREDIT LOSSES AND CREDIT QUALITY - Allowance for loan losses by portfolio segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	$ 67,523	$ 71,713	$ 67,773	$ 61,408
Provision for credit losses	0	1,300	417	1,077
Loans charged-off	(373)	(90)	(1,211)	(593)
Recoveries	89	125	260	2,106
Net loans (charged-off) recovered	(284)	35	(951)	1,513
Ending balance	67,239	73,048	67,239	73,048
Impact of adopting ASC 326 \| ASU 2016-13
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance				9,050
Unallocated
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	647	506	450	3,139
Provision for credit losses	(22)	(126)	175	122
Loans charged-off	0	0	0	0
Recoveries	0	0	0	0
Net loans (charged-off) recovered	0	0	0	0
Ending balance	625	380	625	380
Unallocated \| Impact of adopting ASC 326 \| ASU 2016-13
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance				(2,881)
Commercial Portfolio Segment \| Commercial and Industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	31,195	33,130	30,595	28,333
Provision for credit losses	1,357	3,507	1,948	2,780
Loans charged-off	(222)	(5)	(254)	(254)
Recoveries	18	44	59	1,505
Net loans (charged-off) recovered	(204)	39	(195)	1,251
Ending balance	32,348	36,676	32,348	36,676
Commercial Portfolio Segment \| Commercial and Industrial \| Impact of adopting ASC 326 \| ASU 2016-13
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance				4,312
Commercial Portfolio Segment \| Commercial Real Estate and Multifamily Residential
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	26,448	28,291	26,535	22,907
Provision for credit losses	(678)	(1,545)	(168)	(420)
Loans charged-off	0	0	(597)	(71)
Recoveries	25	0	25	14
Net loans (charged-off) recovered	25	0	(572)	(57)
Ending balance	25,795	26,746	25,795	26,746
Commercial Portfolio Segment \| Commercial Real Estate and Multifamily Residential \| Impact of adopting ASC 326 \| ASU 2016-13
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance				4,316
Commercial Portfolio Segment \| Agri-business and Agricultural
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	4,753	3,930	5,034	3,043
Provision for credit losses	(547)	(244)	(828)	(737)
Loans charged-off	0	0	0	0
Recoveries	0	0	0	320
Net loans (charged-off) recovered	0	0	0	320
Ending balance	4,206	3,686	4,206	3,686
Commercial Portfolio Segment \| Agri-business and Agricultural \| Impact of adopting ASC 326 \| ASU 2016-13
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance				1,060
Commercial Portfolio Segment \| Other Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	713	1,298	1,146	416
Provision for credit losses	16	89	(417)	30
Loans charged-off	0	0	0	0
Recoveries	0	0	0	0
Net loans (charged-off) recovered	0	0	0	0
Ending balance	729	1,387	729	1,387
Commercial Portfolio Segment \| Other Commercial \| Impact of adopting ASC 326 \| ASU 2016-13
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance				941
Consumer Portfolio Segment \| Consumer 1-4 Family Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	2,674	3,165	2,866	2,619
Provision for credit losses	(197)	(265)	(411)	(719)
Loans charged-off	(20)	(13)	(42)	(51)
Recoveries	3	14	47	99
Net loans (charged-off) recovered	(17)	1	5	48
Ending balance	2,460	2,901	2,460	2,901
Consumer Portfolio Segment \| Consumer 1-4 Family Mortgage \| Impact of adopting ASC 326 \| ASU 2016-13
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance				953
Consumer Portfolio Segment \| Other Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	1,093	1,393	1,147	951
Provision for credit losses	71	(116)	118	21
Loans charged-off	(131)	(72)	(318)	(217)
Recoveries	43	67	129	168
Net loans (charged-off) recovered	(88)	(5)	(189)	(49)
Ending balance	$ 1,076	$ 1,272	$ 1,076	1,272
Consumer Portfolio Segment \| Other Consumer \| Impact of adopting ASC 326 \| ASU 2016-13
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance				$ 349

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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Amount, excluding accrued interest, of decrease (increase) in allowance for credit loss on financing receivable from writeoff (recovery). Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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