STOCK-BASED COMPENSATION PLANS - Stock Units Activity (Details) - $ / shares	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Performance stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period (in years)	3 years	3 years
Units vested and exercised	33,083	25,041
Number of Units Outstanding
Beginning balance (in shares)	56,328	43,058
Awarded (in shares)	33,083	25,041
Vested (in shares)	(7,694)	(10,369)
Forfeited (in shares)	(11,252)	(1,402)
Ending balance (in shares)	70,465	56,328
Weighted Average Grant Date Fair Value
Beginning balance (usd per share)	$ 24.98	$ 26.01
Granted (usd per share)	23.18	25.07
Vested (usd per share)	26.79	18.51
Forfeited (usd per share)	25.33	29.13
Ending balance (usd per share)	$ 23.88	$ 24.98
Performance stock units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant under this plan	0	0
Performance stock units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant under this plan	49,625	37,562
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years	3 years
Units vested and exercised	59,401	63,667
Number of Units Outstanding
Beginning balance (in shares)	131,398	106,552
Awarded (in shares)	59,401	63,667
Vested (in shares)	(38,202)	(31,565)
Forfeited (in shares)	(18,980)	(7,256)
Ending balance (in shares)	133,617	131,398
Weighted Average Grant Date Fair Value
Beginning balance (usd per share)	$ 23.57	$ 25.82
Granted (usd per share)	25.51	21.98
Vested (usd per share)	27.33	27.38
Forfeited (usd per share)	22.72	25.60
Ending balance (usd per share)	$ 23.48	$ 23.57
Restricted stock units \| Certain prior executives and senior officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years	3 years
Weighted Average Grant Date Fair Value
Granted (usd per share)	$ 22.51	$ 20.44
Restricted stock units \| Senior vice presidents cliff
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years	3 years
Weighted Average Grant Date Fair Value
Granted (usd per share)	$ 28.93	$ 25.07
Cash based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units vested and exercised	20,568	13,290
Number of Units Outstanding
Awarded (in shares)	20,568	13,290

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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