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BENEFIT PLANS - Deferred Compensation Plans for Directors (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Deferred Compensation Arrangements [Abstract] |  |  |
Liability accrued for compensation plan | $ 9,127 | $ 10,120 |
Deferred Compensation Plans for Directors [Member] | Directors [Member] |  |  |
Deferred Compensation Arrangements [Abstract] |  |  |
Deferred compensation arrangement with individual, shares credited (in shares) | 141,655 | 151,519 |
Liability accrued for compensation plan | $ 4,800 | $ 4,900 |
Expense recognized under plan | $ 200 | $ 200 | $ 200

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- Definition Amount of expense recognized from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments), awarded to key employees or individuals. Excludes amount related to plans that cover generally all employees (for example, but not limited to, qualified pension plans). + References No definition available. + Details
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- Definition The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 710 -SubTopic 10 -Section 30 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363 + Details
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- Definition Number of shares issued pursuant to the terms of a deferred compensation 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 (l) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- References No definition available. + Details
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