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EMPLOYEE BENEFIT PLANS - Plan summary (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2019
Nonunion Defined Benefit Pension Plan |  |
Postretirement benefit plans |  |
Noncash charge to pension settlement expense |  | $ 4.0
Noncash charge to pension settlement expense, tax benefit |  | $ 0.0
Postretirement Health Benefit Plan |  |
Postretirement benefit plans |  |
Unrecognized prior service credit, amortization period | 9 years |

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- Definition The period over which the unrecognized prior service cost (credit) is being amortized. + References No definition available. + Details
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- Definition Tax impact of amount of noncash expense (reversal of expense) for pension benefits. Excludes other postretirement benefits. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of noncash expense (reversal of expense) for pension benefits. Excludes other postretirement benefits. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 + Details
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- Details
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- Details
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