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STOCK-BASED COMPENSATION PLANS - Long-Term Incentive Program (Details) - USD ($) $ in Millions |  |  |  | 12 Months Ended |
--- | --- | --- | --- | --- | ---
May 17, 2017 | May 14, 2014 | May 25, 2011 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | May 18, 2022
Share-based Arrangements with Employees and Nonemployees |  |  |  |  |  |  |
Shares of common stock authorized for stock-based compensation plan (in shares) |  |  |  | 4,000,000 |  |  |
Additional shares of common stock authorized for stock-based compensation plan (in shares) | 1,000,000 | 1,000,000 | 900,000 |  |  |  |
Number of shares available for grant (in shares) |  |  |  | 600,000 |  |  | 600,000
Nonqualified Stock Option [Member] |  |  |  |  |  |  |
Share-based Arrangements with Employees and Nonemployees |  |  |  |  |  |  |
Income tax benefit |  |  |  | $ 0.8 | $ 0.7 | $ 0.6 |
Stock-based compensation expense related to incentive and non-qualified stock options recognized |  |  |  | $ 3.2 | $ 2.9 | $ 2.6 |
Employee Stock Option [Member] |  |  |  |  |  |  |
Share-based Arrangements with Employees and Nonemployees |  |  |  |  |  |  |
Term of options |  |  |  | 10 years |  |  |
Award vesting period |  |  |  | 5 years |  |  |
Director's Stock Balance Plan [Member] | Nonqualified Stock Option [Member] |  |  |  |  |  |  |
Share-based Arrangements with Employees and Nonemployees |  |  |  |  |  |  |
Term of options |  |  |  | 1 year |  |  |
Term of options in event of death |  |  |  | 2 years |  |  |

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- Definition Period from grant date that an equity-based award expires in the event of death, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479830/718-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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