Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
		Feb. 28, 2021	Feb. 29, 2020	Feb. 28, 2021	Feb. 29, 2020
Income Statement [Abstract]
Net Sales		$ 1,269,395	$ 1,173,976	$ 4,361,981	$ 4,048,033
Cost of Sales		797,454	739,229	2,650,213	2,509,133
Gross Profit		471,941	434,747	1,711,768	1,538,900
Selling, General and Administrative Expenses		402,186	381,866	1,197,556	1,185,791
Restructuring Charges		3,129	7,343	12,280	18,766
Interest Expense		20,964	23,972	63,975	78,630
Investment (Income) Expense, Net		(11,454)	3,836	(33,735)	(10,354)
Other Expense, Net		1,256	1,422	7,507	5,158
Income Before Income Taxes		55,860	16,308	464,185	260,909
Provision for Income Taxes		17,394	4,218	117,049	65,002
Net Income		38,466	12,090	347,136	195,907
Less: Net Income Attributable to Noncontrolling Interests		224	237	640	835
Net Income Attributable to RPM International Inc. Stockholders		$ 38,242	$ 11,853	$ 346,496	$ 195,072
Average Number of Shares of Common Stock Outstanding:
Basic		128,447	128,426	128,455	128,572
Diluted	[1]	129,949	130,028	129,052	129,238
Earnings per Share of Common Stock Attributable to RPM International Inc. Stockholders:
Basic		$ 0.30	$ 0.09	$ 2.68	$ 1.51
Diluted		$ 0.29	$ 0.09	$ 2.66	$ 1.50

[1] Restricted shares totaling 225,500 and 231,450 for the three and nine months ended February 28, 2021, respectively, were excluded from the calculation of diluted earnings per share as their effect would have been anti-dilutive. There were no shares of restricted stock identified as being anti-dilutive for the three or nine months ended February 29, 2020.  In addition, stock appreciation rights (“SARs”) totaling 360,000 and for the three and nine months ended February 28, 2021 were excluded from the calculation of diluted earnings per share as their effect would have been anti-dilutive.  There were no SARs identified as being anti-dilutive for the three or nine months ended February 29, 2020.