The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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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.

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Amount of loss contingency liability expected to be resolved within one year or the normal operating cycle, if longer.

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Amount of the obligation recognized by withdrawing from a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

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The deductible retentions per occurrence for auto, workers' compensation and general liability insurance programs.

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COMMITMENTS AND CONTINGENCIES (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Loss Contingencies [Line Items]
Withdrawal obligation	$ 1.4
Letter of Credit \| Line of Credit
Loss Contingencies [Line Items]
Undrawn standby letters of credit	25.9
Long-term line of credit	1.1
Insurance Claims
Loss Contingencies [Line Items]
Amount accrued for self-insurance claims	34.9	$ 33.0
Performance bonds
Loss Contingencies [Line Items]
Contingent liability for performance	12.9
Minimum \| Workers' Compensation Insurance and General Liability
Loss Contingencies [Line Items]
Deductible retention per occurrence	1.0
Minimum \| Automobile Insurance
Loss Contingencies [Line Items]
Deductible retention per occurrence	2.0
Maximum \| Workers' Compensation Insurance and General Liability
Loss Contingencies [Line Items]
Deductible retention per occurrence	2.0
Maximum \| Automobile Insurance
Loss Contingencies [Line Items]
Deductible retention per occurrence	$ 10.0