Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Nov. 30, 2016	Nov. 30, 2015	Nov. 30, 2016	Nov. 30, 2015
Statement Of Income And Comprehensive Income [Abstract]
Net (Loss) Income	$ (70,256)	$ 84,149	$ 43,138	$ 184,511
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	(51,984)	(53,814)	(63,495)	(84,420)
Pension and other postretirement benefit liability adjustments (net of tax of $1,963; $1,803; $4,762; $3,817, respectively)	3,590	3,640	9,294	7,800
Unrealized gain (loss) on securities (net of tax of $(320); $632; $776; $(2,595), respectively)	(895)	369	709	(6,715)
Total other comprehensive (loss)	(49,289)	(49,805)	(53,492)	(83,335)
Total Comprehensive (Loss) Income	(119,545)	34,344	(10,354)	101,176
Less: Comprehensive Income Attributable to Noncontrolling Interests	670	716	1,295	1,263
Comprehensive (Loss) Income Attributable to RPM International Inc. Stockholders	$ (120,215)	$ 33,628	$ (11,649)	$ 99,913

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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