ACQUISITIONS	6 Months Ended
Jun. 30, 2026
Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]
Business Combination Disclosure [Text Block]	NOTE 3. ACQUISITIONS On April 18, 2025, Olin acquired AMMO, Inc.’s small caliber ammunition manufacturing assets for total consideration of $55.8 million. The acquisition, which includes AMMO Inc.’s brass shellcase capabilities and its 185,000 square foot production facility located in Manitowoc, WI, is included in Olin’s Winchester segment. The acquisition was financed with cash on hand. We recorded the final aggregate excess purchase price over the fair value of identifiable tangible assets acquired and liabilities assumed, which included a final allocation of $4.1 million of goodwill allocated to our Winchester segment. The total assets acquired, excluding goodwill, and liabilities assumed amounted to $62.2 million and $6.4 million, respectively. The acquisition is not material and therefore supplemental pro forma financial information is not provided. On June 15, 2026, Olin entered into a definitive agreement with Huntsman Corporation (Huntsman) to combine in an all-stock merger of equals transaction (the Merger Agreement) to form a combined company, OlinHuntsman Corporation. Pursuant to the terms of the Merger Agreement, at the effective time of the transaction, each issued and outstanding share of Huntsman common stock will be converted into the right to receive 0.5476 shares of Olin common stock. Upon completion of the transaction, existing Olin shareholders are expected to own approximately 54.5% of the combined company and existing Huntsman stockholders are expected to own approximately 45.5% of the combined company. The consummation of the merger is subject to the satisfaction of customary closing conditions, including the receipt of required regulatory approvals and approval of the merger by both Olin shareholders and Huntsman stockholders. The transaction is expected to close in the first half of 2027. For both the three and six months ended June 30, 2026, we incurred acquisition-related costs of $10.6 million which included costs associated with advisory, legal, accounting, and other professional fees.

On April 18, 2025, Olin acquired AMMO, Inc.’s small caliber ammunition manufacturing assets for total consideration of $55.8 million. The acquisition, which includes AMMO Inc.’s brass shellcase capabilities and its 185,000 square foot production facility located in Manitowoc, WI, is included in Olin’s Winchester segment. The acquisition was financed with cash on hand. We recorded the final aggregate excess purchase price over the fair value of identifiable tangible assets acquired and liabilities assumed, which included a final allocation of $4.1 million of goodwill allocated to our Winchester segment. The total assets acquired, excluding goodwill, and liabilities assumed amounted to $62.2 million and $6.4 million, respectively. The acquisition is not material and therefore supplemental pro forma financial information is not provided.

On June 15, 2026, Olin entered into a definitive agreement with Huntsman Corporation (Huntsman) to combine in an all-stock merger of equals transaction (the Merger Agreement) to form a combined company, OlinHuntsman Corporation.

Pursuant to the terms of the Merger Agreement, at the effective time of the transaction, each issued and outstanding share of Huntsman common stock will be converted into the right to receive 0.5476 shares of Olin common stock. Upon completion of the transaction, existing Olin shareholders are expected to own approximately 54.5% of the combined company and existing Huntsman stockholders are expected to own approximately 45.5% of the combined company.

The consummation of the merger is subject to the satisfaction of customary closing conditions, including the receipt of required regulatory approvals and approval of the merger by both Olin shareholders and Huntsman stockholders. The transaction is expected to close in the first half of 2027.

For both the three and six months ended June 30, 2026, we incurred acquisition-related costs of $10.6 million which included costs associated with advisory, legal, accounting, and other professional fees.