STOCK-BASED COMPENSATION - Summary of restricted stock (Details) - USD ($) $ / shares in Units, $ in Thousands	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Non-performance based restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares underlying restricted stock	92,960	83,563	157,711	129,667
Weighted-average grant date fair value per share	$ 27.86	$ 27.85	$ 27.26	$ 28.22
Aggregate fair value (in thousands)	$ 2,719
Performance-based restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares underlying restricted stock	2,250	2,250	2,250	2,250
Weighted-average grant date fair value per share	$ 34.40	$ 34.40	$ 34.40	$ 34.40
Aggregate fair value (in thousands)	$ 66

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.

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)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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