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STOCK-BASED COMPENSATION PLANS - Long-Term Incentive Program (Details) - shares |  |  |  | 12 Months Ended
--- | --- | --- | --- | ---
May 17, 2017 | May 14, 2014 | May 25, 2011 | Dec. 31, 2020
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) |  |  |  | 800,000
Stock Options [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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- References No definition available. + 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Number of additional shares authorized for issuance under share-based payment arrangement. + References No definition available. + Details
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- Definition Number of shares authorized for issuance under share-based payment arrangement. + 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 (a)(3) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition 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. + 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 + Details
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- Definition Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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 (a)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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