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ACQUISITIONS - Intangible asset, goodwill and acquisition related expenses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	May 13, 2022
Identifiable Intangible Assets
Merger and acquisition integration related (recoveries) expenses	$ 0	$ 409	$ 56	$ 4,668
Other intangibles
Identifiable Intangible Assets
Intangible asset useful life (amortization period)	10 years		10 years
Elmira Savings Bank ("Elmira")
Identifiable Intangible Assets
Federal Home Loan Bank of New York borrowings					$ 17,600
Weighted-average rate					2.48%
Axiom | Core deposit intangibles
Identifiable Intangible Assets
Intangible asset useful life (amortization period)	8 years		8 years

X

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479405/805-10-25-23

+ Details

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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- Definition

Amount of Federal Home Loan Bank (FHLBank) advances to member financial institutions.

+ References

No definition available.

+ Details

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- References

No definition available.

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- Details

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