STOCK-BASED COMPENSATION PLANS - Outstanding and exercisable number of stock options (Details) shares in Thousands	Sep. 30, 2021 shares
Share-based Compensation Arrangement by Share-based Payment Award
Outstanding Number of Options (in shares)	708
Exercisable Number of Options	588
2005 Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award
Outstanding Number of Options (in shares)	295
Exercisable Number of Options	295
Equity Compensation Plans not approved by Shareholders
Share-based Compensation Arrangement by Share-based Payment Award
Outstanding Number of Options (in shares)	25
Exercisable Number of Options	25
2017 Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award
Outstanding Number of Options (in shares)	388
Exercisable Number of Options	268

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ 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
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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