SUBSEQUENT EVENT (Details) - Subsequent Event T in Millions, $ in Millions	Feb. 24, 2020 USD ($) T
Coram Material Corp.
Subsequent Event [Line Items]
Remaining purchase price, term (years)	2 years
Total consideration for acquisitions	$ 142.0
Proven and permitted reserves acquired \| T	41.9
Proven and unpermitted reserves acquired \| T	7.5
Remaining purchase price	$ 2.0
Third Loan Agreement \| Line of Credit \| Revolving Facility
Subsequent Event [Line Items]
Proceeds from draws on line of credit	$ 140.0

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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