RELATED PARTY TRANSACTIONS	3 Months Ended
RELATED PARTY TRANSACTIONS	Dec. 31, 2025
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTIONS	RELATED PARTY TRANSACTIONS For the three months ended December 31, 2025 and December 31, 2024, the Company recorded approximately $0.5 million and $1.1 million, respectively, in SOP sales to certain subsidiaries of Koch Industries, Inc., which are considered related parties. As of both December 31, 2025 and September 30, 2025, the Company recorded approximately $0.2 million of receivables from related parties in its Condensed Consolidated Balance Sheets. The Company had no related-party payables outstanding as of December 31, 2025 and December 31, 2024. Effective December 18, 2025, a new member was appointed to the Company’s board of directors. The new director also serves as President and Chief Executive Officer of another company from which the Company purchased approximately $1.1 million of salt-treatment materials during the three months ended December 31, 2025, constituting a related party transaction. In addition, the Company has a payable of approximately $0.3 million outstanding as of December 31, 2025, related to this transaction.

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

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COMPASS MINERALS INTERNATIONAL INC 10-Q