STOCK-BASED COMPENSATION - Restricted stock activity (Details) - $ / shares	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021
Performance-based restricted stock
Number of Shares
Outstanding, beginning of period	2,250	2,250
Outstanding, end of period	2,250	2,250
Weighted Average Grant Date Fair Value
Outstanding, beginning of period	$ 34.40	$ 34.40
Outstanding, end of period	$ 34.40	$ 34.40
Non-performance based restricted stock
Number of Shares
Outstanding, beginning of period	83,563	129,667
Granted	38,457	51,665
Vested	(27,083)	(22,210)
Forfeited	(1,977)	(1,411)
Outstanding, end of period	92,960	157,711
Weighted Average Grant Date Fair Value
Outstanding, beginning of period	$ 27.85	$ 28.22
Granted	29.42	26.31
Vested	29.70	30.57
Forfeited	33.04	28.82
Outstanding, end of period	$ 27.86	$ 27.26

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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