Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Feb. 28, 2023	Feb. 28, 2022	Feb. 28, 2023	Feb. 28, 2022
Statement of Comprehensive Income [Abstract]
Net Income	$ 27,239	$ 33,249	$ 328,060	$ 293,160
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments (net of tax of $72; $296; $2,263 and $3,562, respectively)	(6,935)	16,124	(76,719)	(69,722)
Pension and other postretirement benefit liability adjustments (net of tax of $1,132; $951; $3,637 and $3,630, respectively)	3,606	3,057	11,427	11,086
Unrealized (loss) gain on securities and other (net of tax oUnrealized gain (loss) on securities and other (net of tax of $199; $238; $405 and $473, respectively)	107	(384)	(467)	(287)
Unrealized (loss) gain on derivatives (net of tax of zero; $838; zero and $6,551, respectively)	(555)	2,648	(1,765)	21,448
Total other comprehensive (loss) income	(3,777)	21,445	(67,524)	(37,475)
Total Comprehensive Income	23,462	54,694	260,536	255,685
Less: Comprehensive Income Attributable to Noncontrolling Interests	263	238	689	633
Comprehensive Income Attributable to RPM International Inc. Stockholders	$ 23,199	$ 54,456	$ 259,847	$ 255,052