BUSINESS COMBINATION - Additional Information (Narrative) (Details) - Coram Material Corp. T in Millions, $ in Millions		6 Months Ended
Feb. 24, 2020 a T	Jun. 30, 2020 USD ($)
Business Acquisition [Line Items]
Area of land (acres) \| a	330
Area of land, mining acres (acres) \| a	180
Proven aggregate reserves (tons) \| T	41.9
Proven but unpermitted aggregate reserves (tons) \| T	7.5
Transaction costs \| $		$ 0.6

Area of land held.

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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

For transactions that are recognized separately from the acquisition of assets and assumptions of liabilities in the business combination, such as related to pre-existing relationships with the acquiree, this element represents the disclosure of the amount of acquisition related costs which have been expensed.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

Area Of Land, Mining Acres

+ References

No definition available.

+ Details

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- Definition

Business Combination, Proven And Permitted Reserves Acquired

+ References

No definition available.

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- Definition

Business Combination, Proven And Unpermitted Reserves Acquired

+ References

No definition available.

+ Details

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- Details

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