STOCK-BASED COMPENSATION PLANS - Activity of unvested Restricted Stock Awards (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Restricted Shares
Unvested, beginning of period (in shares)	47,820	48,976
Awards (in shares)	35,815	0
Forfeitures (in shares)	(51,000)	(578)
Vestings (in shares)	(636)	(578)
Unvested, end of period (in shares)	31,999	47,820	48,976
Weighted-average grant date fair value
Unvested, beginning of period (in dollars per share)	$ 29.71	$ 29.71
Awards (in dollars per share)	34.93	0.00
Forfeitures (in dollars per share)	30.02	29.71
Vestings (in dollars per share)	35.89	29.71
Unvested, end of period (in dollars per share)	$ 34.93	$ 29.71	$ 29.71
Restricted Stock
Restricted Shares
Unvested, beginning of period (in shares)	129,448	127,432
Awards (in shares)	56,871	51,456
Forfeitures (in shares)	(2,940)	(2,041)
Vestings (in shares)	(49,859)	(47,399)
Unvested, end of period (in shares)	133,520	129,448	127,432
Weighted-average grant date fair value
Unvested, beginning of period (in dollars per share)	$ 64.32	$ 53.97
Awards (in dollars per share)	71.58	79.51
Forfeitures (in dollars per share)	67.44	55.39
Vestings (in dollars per share)	62.86	53.13
Unvested, end of period (in dollars per share)	$ 67.89	$ 64.32	$ 53.97
Unrecognized stock-based compensation expense	$ 6,400
Award vesting period	5 years
Weighted-average period for recognition of unrecognized compensation cost	2 years 4 months 24 days
Total fair value of restricted stock vested	$ 3,100	$ 2,500	$ 2,700
Vesting period	5 years
Performance Awards
Restricted Shares
Unvested, end of period (in shares)	31,999
Weighted-average grant date fair value
Unrecognized stock-based compensation expense	$ 700
Award vesting period	3 years
Weighted-average period for recognition of unrecognized compensation cost	2 years
Total fair value of restricted stock vested	$ 20	10	100
Stock-based compensation expense	$ 3,800	$ 2,800	$ 2,700
Vesting period	3 years
Performance Awards \| Granted prior to 2022
Weighted-average grant date fair value
Award vesting period	5 years
Vesting period	5 years
Performance Awards \| Granted in 2022 and thereafter
Weighted-average grant date fair value
Award vesting period	3 years
Vesting period	3 years

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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-Publisher FASB
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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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

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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).

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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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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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