BUSINESS COMBINATION - Consideration (Details) - KMG $ in Thousands	Nov. 15, 2018 USD ($)
Business Combination, Consideration Transferred [Abstract]
Total cash consideration paid for KMG outstanding common stock and equity awards	$ 900,756
Cash provided to payoff KMG debt	304,648
Total cash consideration paid	1,205,404
Fair value of CMC common stock issued for KMG outstanding common stock and equity awards	331,048
Total consideration transferred	$ 1,536,452

Payments to Acquire Businesses, Gross, Debt

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Payments to Acquire Businesses, Gross, Equity

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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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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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