Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Feb. 29, 2016	Feb. 28, 2015	Feb. 29, 2016	Feb. 28, 2015
Statement Of Income And Comprehensive Income [Abstract]
Net Income (Loss)	$ 19,293	$ (78,952)	$ 203,804	$ 99,743
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	(16,214)	(79,275)	(100,634)	(191,763)
Pension and other postretirement benefit liability adjustments (net of tax of $1,827; $2,497; $5,645; $6,225, respectively)	3,264	6,511	11,064	14,425
Unrealized (loss) on securities (net of tax of $(3,376); $(1,560); $(5,971); $(2,715), respectively)	(7,334)	(3,488)	(14,049)	(5,979)
Unrealized gain on derivatives (net of tax of $0; $85; $0; $119, respectively)		420		637
Total other comprehensive (loss)	(20,284)	(75,832)	(103,619)	(182,680)
Total Comprehensive Income (Loss)	(991)	(154,784)	100,185	(82,937)
Less: Comprehensive Income (Loss) Attributable to Noncontrolling Interests	711	(21,728)	1,974	(16,340)
Comprehensive Income (Loss) Attributable to RPM International Inc. Stockholders	$ (1,702)	$ (133,056)	$ 98,211	$ (66,597)