Document and Entity Information	3 Months Ended
	Aug. 31, 2014	Oct. 06, 2014
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Aug. 31, 2014
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Trading Symbol	RPM
Entity Registrant Name	RPM INTERNATIONAL INC/DE/
Entity Central Index Key	0000110621
Current Fiscal Year End Date	--05-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		133,476,101