STOCK BASED COMPENSATION PLANS - Exercise Prices (Details) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options	180,020	110,660
Exercise Price	$ 35.39	$ 35.71
$34.87
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options	69,360
Exercise Price	$ 34.87
$35.35
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options	63,267
Exercise Price	$ 35.35
36.19
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options	47,393
Exercise Price	$ 36.19

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No definition available.

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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