Subsequent Events	9 Months Ended
Feb. 28, 2026
Subsequent Events [Abstract]
Subsequent Events	NOTE 18 — SUBSEQUENT EVENTS Stock Repurchase Subsequent to February 28, 2026, we repurchased 246,321 shares of RPM common stock at a cost of approximately $25.0 million, or an average of $101.49 per share, under the stock repurchase program described in Note 10, "Stock Repurchase Program." Business Acquisition On March 31, 2026, we completed the previously announced acquisition of Kalzip GmbH ("Kalzip"), a global leader in the design and production of metal-based roofs and facades for building envelopes. Kalzip generated net sales of approximately €75.0 million in calendar year 2024 and will be included in our CPG reportable segment.

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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