COMMITMENTS AND CONTINGENCIES (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Loss Contingencies [Line Items]
Estimated Project Capital Expenditures	$ 830.0
Project Spend Contingency Percentage	20.00%
Unrecorded Unconditional Purchase Obligation, Due in Next Twelve Months	$ 290.0
Accrual for Environmental Loss Contingencies	2.0	$ 2.5
Capital Addition Purchase Commitments [Member]
Loss Contingencies [Line Items]
Unrecorded Unconditional Purchase Obligation	$ 260.0

Estimated Project Capital Expenditures [Member]

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- Definition

Project Spend Contingency Percentage

+ References

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- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
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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.

+ References

No definition available.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 440
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-Section 50
-Paragraph 4
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- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

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