ACQUISITIONS - Summary of Loans Acquired (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Elmira transaction \| Non-PCD Loans
Certain Loans Acquired During The Period
Unpaid principal balance of non-PCD loans	$ 455,700
Net discount on fair value adjustments of non-PCD loans	20,800
Steuben Trust Corporation \| Acquired Impaired
Certain Loans Acquired During The Period
Par value of PCD loans at acquisition	2,184
Allowance for credit losses at acquisition	(71)
Non-credit (discount)/premium at acquisition	81
Fair value of PCD loans at acquisition	2,032
Steuben Trust Corporation \| Non-PCD Loans
Certain Loans Acquired During The Period
Par value of PCD loans at acquisition		$ 35,906
Allowance for credit losses at acquisition		(668)
Non-credit (discount)/premium at acquisition		(103)
Fair value of PCD loans at acquisition		$ 35,341
Unpaid principal balance of non-PCD loans	313,000
Net premium on fair value adjustments of non-PCD loans	$ 2,500

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

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