Subsequent Events	6 Months Ended
Nov. 30, 2025
Subsequent Events [Abstract]
Subsequent Events	NOTE 18 — SUBSEQUENT EVENTS SG&A-Focused Optimization Actions Subsequent to November 30, 2025, we developed and began to implement SG&A-focused optimization actions designed to better align our cost and expense structure with current market demand. This will include reduction in headcount and other discretionary spending. We are still finalizing the total expected cost to implement these optimization actions, but we expect the cost to be at least $20.0 million. Business Acquisition Subsequent to November 30, 2025, RPM entered into a definitive agreement to acquire Kalzip GmbH ("Kalzip"), a global leader in the design and production of metal-based roofs and facades for building envelopes, which was announced on January 7, 2026. Kalzip generated net sales of approximately €75.0 million in calendar year 2024 and will be included in our CPG reportable segment. The transaction is expected to close in the fourth quarter of fiscal 2026, subject to customary closing conditions.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/855/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

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