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ASSET RETIREMENT AND ENVIRONMENTAL OBLIGATIONS (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Unusual Risk or Uncertainty [Line Items]
Asset retirement obligation, current	$ 0.2	$ 0.2
Estimated undiscounted cash flows, to satisfy obligation	$ 52.5	50.2
Remediation term	23 years
Discount rate	2.93%
Environmental obligations, undiscounted cost	$ 26.3	26.7
Environmental obligations, current	0.5	0.5
Closure and reclamation obligations, financial assurances	$ 45.5	$ 45.4
Minimum
Unusual Risk or Uncertainty [Line Items]
Asset retirement obligations, credit-adjusted risk free rate	6.50%
Maximum
Unusual Risk or Uncertainty [Line Items]
Asset retirement obligations, credit-adjusted risk free rate	12.00%

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- Definition

Accrual for Environmental Loss Contingencies, Remediation Term

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Asset Retirement Obligation, Closure And Reclamation Obligations, Financial Assurances

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Asset Retirement Obligations, Credit-Adjusted Risk Free Rate

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Asset Retirement Obligations, Estimated Undiscounted Cash Flows To Satisfy Obligation

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- Definition

Rate applied to the undiscounted amount of environmental loss contingencies to arrive at the present value recorded as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.Y.Q1)
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 410
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
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Undiscounted amount of the accrual for environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
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-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481931/410-30-50-7

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Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 410
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Current portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
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