RPM International (RPM) 10-Q 9 Oct 13 2014 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Aug. 31, 2013	Oct. 04, 2013
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Aug-13
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	Q1
Trading Symbol	RPM
Entity Registrant Name	RPM INTERNATIONAL INC/DE/
Entity Central Index Key	110621
Current Fiscal Year End Date	-26
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		132,945,182

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Aug. 31, 2013	31-May-13
In Thousands, unless otherwise specified
Current Assets
Cash and cash equivalents	$204,903	$343,554
Trade accounts receivable (less allowances of $29,082 and $28,904, respectively)	861,920	787,517
Inventories	572,148	548,680
Deferred income taxes	38,427	36,565
Prepaid expenses and other current assets	172,410	169,956
Total current assets	1,849,808	1,886,272
Property, Plant and Equipment, at Cost	1,126,641	1,128,123
Allowance for depreciation and amortization	-641,494	-635,760
Property, plant and equipment, net	485,147	492,363
Other Assets
Goodwill	1,108,387	1,113,831
Other intangible assets, net of amortization	461,717	459,613
Other	158,067	163,447
Total other assets	1,728,171	1,736,891
Total Assets	4,063,126	4,115,526
Current Liabilities
Accounts payable	394,138	478,185
Current portion of long-term debt	4,537	4,521
Accrued compensation and benefits	108,248	154,844
Accrued loss reserves	26,966	27,591
Other accrued liabilities	226,287	262,889
Total current liabilities	760,176	928,030
Long-Term Liabilities
Long-term debt, less current maturities	1,419,607	1,369,176
Other long-term liabilities	423,321	417,160
Deferred income taxes	36,295	46,227
Total long-term liabilities	1,879,223	1,832,563
Stockholders' Equity
Preferred stock, par value $0.01; authorized 50,000 shares; none issued
Common stock, par value $0.01; authorized 300,000 shares; issued 137,457 and outstanding 132,923 as of August 2013; issued 136,913 and outstanding 132,596 as of May 2013	1,329	1,326
Paid-in capital	770,726	763,505
Treasury stock, at cost	-76,497	-72,494
Accumulated other comprehensive (loss)	-174,909	-159,253
Retained earnings	741,035	667,774
Total RPM International Inc. stockholders' equity	1,261,684	1,200,858
Noncontrolling interest	162,043	154,075
Total Equity	1,423,727	1,354,933
Total Liabilities and Stockholders' Equity	$4,063,126	$4,115,526

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Aug. 31, 2013	31-May-13
In Thousands, except Per Share data, unless otherwise specified
Trade accounts receivable, allowances	$29,082	$28,904
Preferred stock, par value	$0.01	$0.01
Preferred stock, authorized	50,000	50,000
Preferred stock, issued
Common stock, par value	$0.01	$0.01
Common stock, authorized	300,000	300,000
Common stock, issued	137,457	136,913
Common stock, outstanding	132,923	132,596

Consolidated_Statements_Of_Inc

Consolidated Statements Of Income (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Aug. 31, 2013		Aug. 31, 2012
Net Sales	$1,164,674		$1,046,714
Cost of Sales	665,602		612,834
Gross Profit	499,072		433,880
Selling, General and Administrative Expenses	335,459		310,940
Interest Expense	20,725		18,430
Investment (Income), Net	-3,894		-6,974
Other (Income) Expense, Net	-434		39,422
Income Before Income Taxes	147,216		72,062
Provision for Income Taxes	40,327		34,195
Net Income	106,889		37,867
Less: Net Income Attributable to Noncontrolling Interests	3,791		3,954
Net Income Attributable to RPM International Inc. Stockholders	$103,098		$33,913
Average Number of Shares of Common Stock Outstanding:
Basic	129,344		128,805
Diluted	130,294		129,570
Earnings per Share of Common Stock Attributable to RPM International Inc. Stockholders
Basic	$0.78		$0.26
Diluted	$0.77	[1]	$0.26	[1]
Cash Dividends Declared per Share of Common Stock	$0.23		$0.22
[1]	For the quarters ended August 31, 2013 and 2012, approximately 3,097,000 and 2,954,000 shares of stock, respectively, granted under stock-based compensation plans were excluded from the calculation of diluted earnings per share, as the effect would have been anti-dilutive.

Consolidated_Statements_Of_Com

Consolidated Statements Of Comprehensive Income (Loss) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Aug. 31, 2013	Aug. 31, 2012
Net income	$106,889	$37,867
Other Comprehensive Income, Net of Tax:
Foreign currency translation adjustments	-13,414	39,230
Pension and Other Postretirement Benefit Liability Adjustments (Net of Tax of $1,586 and $757, respectively)	2,924	1,206
Unrealized (Loss) on Securities (Net of Tax Benefit of $815 and $636, respectively)	-1,439	-352
Unrealized Gain on Derivatives (Net of Tax of $45 and $71, respectively)	109	187
Total Other Comprehensive (Loss) Income	-11,820	40,271
Total Comprehensive Income	95,069	78,138
Less: Comprehensive Income Attributable to Noncontrolling Interests	7,627	13,033
Comprehensive Income Attributable to RPM International Inc. Stockholders	$87,442	$65,105

Consolidated_Statements_Of_Com1

Consolidated Statements Of Comprehensive Income (Loss) (Parenthetical) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Aug. 31, 2013	Aug. 31, 2012
Pension and Other Postretirement Benefit Liability Adjustments, Tax	$1,586	$757
Unrealized (Loss) on Securities, Tax Benefit	815	636
Unrealized Gain on Derivatives, Tax	$45	$71

Consolidated_Statements_Of_Cas

Consolidated Statements Of Cash Flows (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Aug. 31, 2013	Aug. 31, 2012
Cash Flows From Operating Activities:
Net income	$106,889	$37,867
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	14,431	13,330
Amortization	7,882	6,735
Impairment on investment in Kemrock		40,273
Deferred income taxes	-11,505	1,874
Stock-based compensation expense	4,826	3,873
Other	-701	-442
Changes in assets and liabilities, net of effect from purchases and sales of businesses:
(Increase) decrease in receivables	-76,455	7,162
(Increase) in inventory	-23,439	-24,650
(Increase) decrease in prepaid expenses and other current and long-term assets	-7,201	554
(Decrease) in accounts payable	-83,264	-54,226
(Decrease) in accrued compensation and benefits	-46,001	-56,362
(Decrease) in accrued loss reserves	-499	-118
Increase in other accrued liabilities	47,701	53,198
(Decrease) in contingent payment	-61,894
Other	-232	-11,334
Cash (Used For) Provided By Operating Activities	-129,462	17,734
Cash Flows From Investing Activities:
Capital expenditures	-10,696	-12,702
Acquisition of businesses, net of cash acquired	-12,328	-141,203
Purchase of marketable securities	-20,152	-55,744
Proceeds from sales of marketable securities	17,786	51,172
Other	3,092	15,403
Cash (Used For) Investing Activities	-22,298	-143,074
Cash Flows From Financing Activities:
Additions to long-term and short-term debt	53,218	147,547
Reductions of long-term and short-term debt	-1,936	-63,193
Cash dividends	-29,836	-28,281
Repurchase of stock	-4,004	-260
Other	-2,388	803
Cash Provided By Financing Activities	15,054	56,616
Effect of Exchange Rate Changes on Cash and Cash Equivalents	-1,945	10,138
Net Change in Cash and Cash Equivalents	-138,651	-58,586
Cash and Cash Equivalents at Beginning of Period	343,554	315,968
Cash and Cash Equivalents at End of Period	$204,903	$257,382

Consolidation_Noncontrolling_I

Consolidation, Noncontrolling Interests and Basis of Presentation	3 Months Ended
	Aug. 31, 2013
Consolidation, Noncontrolling Interests and Basis of Presentation	NOTE 1 — CONSOLIDATION, NONCONTROLLING INTERESTS AND BASIS OF PRESENTATION
	Our financial statements include all of our majority-owned subsidiaries, except for certain subsidiaries that were deconsolidated on May 31, 2010 (please refer to Note 3). We account for our investments in less-than-majority-owned joint ventures, for which we have the ability to exercise significant influence, under the equity method. Effects of transactions between related companies, except for certain subsidiaries that were deconsolidated, are eliminated in consolidation.
	Noncontrolling interests are presented in our Consolidated Financial Statements as if parent company investors (controlling interests) and other minority investors (noncontrolling interests) in partially-owned subsidiaries have similar economic interests in a single entity. As a result, investments in noncontrolling interests are reported as equity in our consolidated financial statements. Additionally, our Consolidated Financial Statements include 100% of a controlled subsidiary’s earnings, rather than only our share. Transactions between the parent company and noncontrolling interests are reported in equity as transactions between stockholders provided that these transactions do not create a change in control.
	The accompanying unaudited consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q and do not include all of the information and notes required by Generally Accepted Accounting Principles in the U.S. (“GAAP”) for complete financial statements. In our opinion, all adjustments (consisting of normal, recurring accruals) considered necessary for a fair presentation have been included for the three-month periods ended August 31, 2013 and 2012. For further information, refer to the Consolidated Financial Statements and Notes included in our Annual Report on Form 10-K for the year ended May 31, 2013.
	Our business is dependent on external weather factors. Historically, we have experienced strong sales and net income in our first, second and fourth fiscal quarters comprising the three month periods ending August 31, November 30 and May 31, respectively, with weaker performance in our third fiscal quarter (December through February).
	Certain reclassifications have been made to prior year amounts to conform to the current year presentation.

Investment_in_Kemrock_Industri

Investment in Kemrock Industries and Exports Ltd.	3 Months Ended
	Aug. 31, 2013
Investment in Kemrock Industries and Exports Ltd.	NOTE 2 — INVESTMENT IN KEMROCK INDUSTRIES AND EXPORTS LTD.
	Beginning with our fiscal year ended May 31, 2007, we began purchasing shares of Kemrock Industries and Exports Limited (“Kemrock”) common stock. By May 31, 2011, we had acquired a total of approximately 3.2 million shares of Kemrock common stock, for an accumulated cost approximating $24.2 million, which represented approximately 18% of Kemrock’s outstanding shares at that time. Our investment in Kemrock common stock had been classified in other long-term assets on our balance sheet and included with available-for-sale securities, which are carried at fair value based on quoted market prices.
	During fiscal 2012, we increased our ownership in Kemrock to over 20% of Kemrock’s outstanding shares of common stock and changed our accounting for this investment to the equity method. Additionally, during fiscal 2012, we entered into three other, separate agreements with Kemrock. First, we agreed to loan Kemrock $15.0 million, which was to be repaid in cash, or alternatively, goods and commercial materials, no later than September 15, 2012. The loan was classified as a note receivable and was included in prepaid and other current assets in our Consolidated Balance Sheet. Second, we entered into a global depository receipt (“GDR”) Purchase Agreement with Kemrock, whereby we purchased 693,072 GDRs of Kemrock for an aggregate purchase price of approximately $7.2 million. The GDRs were included in our investment in Kemrock, which had a carrying value at the end of fiscal 2012 of $42.2 million, and were classified as other long-term assets in our Consolidated Balance Sheet. Lastly, during fiscal 2012 we invested $22.7 million in 5.5% convertible bonds issued by Kemrock. Our investment in Kemrock’s convertible bonds was accounted for as an available-for-sale security and was classified in other long-term assets in our Consolidated Balance Sheet. The convertible feature embedded in the convertible bonds is accounted for as a derivative under the guidance in ASC 815, “Derivatives and Hedging.”
	At the time of our investment in Kemrock’s convertible bonds, Kemrock was in the midst of major capital expansion for new projects and upcoming technologies, and there were no indications of any adverse business, economic, competitive, or market factors. However, on August 8, 2012, the price of Kemrock’s common stock plunged below our carrying value, declining by approximately 40% from its May 31, 2012 per share price of 531.0 rupees. We later learned that the dramatic drop in Kemrock’s stock price was related to Kemrock’s announcement of declining sales and income, a liquidity problem at Kemrock that stemmed from its explosive growth, combined with the overall tightening of lending practices of banks and credit markets in India. At that time, we also learned that Kemrock was in the process of renegotiating its credit agreements with its banks. Compounding these difficulties for Kemrock was the deterioration in the exchange rate of the Indian rupee against the U.S. dollar and euro, which had a negative impact on Kemrock’s gross profit margin and cash flow as Kemrock procures the majority of its raw material supplies outside of India, but sells its products in Indian rupees. The market value of shares of Kemrock common stock continued to decline significantly, and dropped from 531.0 rupees per share as of May 31, 2012 to 56.70 rupees per share as of November 30, 2012; the majority of which began to occur during the month of August 2012. By the end of our fiscal year ended May 31, 2013, the market value of shares of Kemrock common stock had continued its decline to 43.85 rupees per share.
	We account for our equity method investment in Kemrock under ASC 323, “Investments — Equity Method and Joint Ventures.” As outlined in ASC 323-10-35-32, a decline in the quoted market price below the carrying amount, when combined with other evidence of a loss in value, may be indicative of a loss in value that is other than temporary. Acting upon the premise that a write-down may be required, we considered all available evidence to evaluate the realizable value of our equity investment, including the decline in the market price of shares of Kemrock stock, the financial condition and near term prospects of Kemrock, and the overall economic situation in India. As a result of these factors, we determined that it was appropriate to record an impairment loss during the three months ended August 31, 2012 of approximately $32.1 million on our equity method investment and a loss of $5.0 million for the amount deemed uncollectible on our then-outstanding $10.0 million loan to Kemrock. As the value of the embedded conversion derivative is directly correlated to the market value of Kemrock stock, we wrote-down the embedded conversion feature derivative and recorded an approximate $8.2 million charge to earnings during the three months ended August 31, 2012. The investment losses were classified in other (income) expense, net and the loss recorded on the loan was included in selling, general and administrative expense in our Consolidated Statements of Income. By the end of our fiscal year ended May 31, 2013, we wrote-down our entire equity- method investment in Kemrock for $42.2 million, the full value of the embedded conversion feature for $9.0 million and the full value of our convertible debt investment for $13.7 million.

Deconsolidation_of_Specialty_P

Deconsolidation of Specialty Products Holding Corp. ("SPHC")	3 Months Ended
	Aug. 31, 2013
Deconsolidation of Specialty Products Holding Corp. ("SPHC")	NOTE 3 — DECONSOLIDATION OF SPECIALTY PRODUCTS HOLDING CORP. (“SPHC”)
	On May 31, 2010, Bondex International, Inc. (“Bondex”) and its parent, SPHC, filed Chapter 11 reorganization proceedings in the United States Bankruptcy Court for the District of Delaware. SPHC is our wholly owned subsidiary. In accordance with ASC 810, when a subsidiary becomes subject to the control of a government,
	court, administrator, or regulator, deconsolidation of that subsidiary is generally required. We therefore deconsolidated SPHC and its subsidiaries from our balance sheet as of May 31, 2010, and eliminated the results of SPHC’s operations from our results of operations beginning on that date. We believe we have no responsibility for liabilities of SPHC and Bondex. As a result of the Chapter 11 reorganization proceedings, on a prospective basis we will continue to account for our investment in SPHC under the cost method.
	We had a net receivable from SPHC at May 31, 2010, that we expect may change before the bankruptcy proceedings have been finalized. The potential change relates to our indemnification of an insurer on appeal bonds pertaining to Bondex’s appeal of two asbestos cases that had been underway prior to the bankruptcy filing, neither of which are material in amount. During our fiscal 2012, one of the appeal bonds was satisfied, and during fiscal 2013, the remaining appeal bond was satisfied. Included in the net amount due from SPHC are receivables and payables, which we concluded we have the right to report as a net amount based on several factors, including the fact that all amounts are determinable, the balances are due to and from our subsidiaries, and we have been given reasonable assurance that netting the applicable receivables and payables would remain legally enforceable. We analyzed our net investment in SPHC as of May 31, 2010, which included a review of our advances to SPHC, an assessment of the collectibility of our net receivables due from SPHC, and a computation of the gain to be recorded upon deconsolidation based on the carrying amount of our investment in SPHC. In accordance with GAAP, the gain on deconsolidation related to the carrying amount of net assets of SPHC at May 31, 2010, was calculated in accordance with ASC 810-10-40-5, as follows:
		a)	the aggregate of (1) the fair value of consideration received, (2) the fair value of any retained noncontrolling investment in the former subsidiary at the date the subsidiary is deconsolidated, and (3) the carrying amount of any noncontrolling interest in the former subsidiary; less
		b)	the carrying amount of the former subsidiary’s assets and liabilities.
	In determining the carrying value of any retained noncontrolling investment in SPHC at the date of deconsolidation we considered several factors, including analyses of cash flows combined with various assumptions relating to the future performance of this entity and a discounted value of SPHC’s recorded asbestos-related contingent obligations based on information available to us as of the date of deconsolidation. The discounted cash flow approach relies primarily on Level 3 unobservable inputs, whereby expected future cash flows are discounted using a rate that includes assumptions regarding an entity’s average cost of debt and equity, incorporates expected future cash flows based on internal business plans, and applies certain assumptions about risk and uncertainties due to the bankruptcy filing. Our estimates are based upon assumptions we believe to be reasonable, but which by nature are uncertain and unpredictable. As a result of this analysis, we determined that the carrying value of our retained interest in SPHC approximated zero.
	As a result of the combined analyses of each of the components of our net investment in SPHC, we recorded a net loss of approximately $7.9 million, which was reflected in Other Expense, Net, during the fourth fiscal quarter of the year ended May 31, 2010. No changes have been made to these amounts through August 31, 2013.

New_Accounting_Pronouncements

New Accounting Pronouncements	3 Months Ended
	Aug. 31, 2013
New Accounting Pronouncements	NOTE 4 — NEW ACCOUNTING PRONOUNCEMENTS
	In February 2013, the FASB further amended the disclosure requirements for comprehensive income. The update requires companies to disclose items reclassified out of accumulated other comprehensive income and into net income in a single location either in the notes to the consolidated financial statements or parenthetically on the face of the Statements of Operations. The change is effective for fiscal years, and interim periods within those years, beginning after December 15, 2012, and is to be applied prospectively. Our adoption of these provisions on June 1, 2013 did not affect our consolidated results of operations, financial condition or liquidity.

Investment_Income_Expense_Net

Investment (Income) Expense, Net	3 Months Ended
	Aug. 31, 2013
Investment (Income) Expense, Net	NOTE 5 — INVESTMENT (INCOME) EXPENSE, NET
	Investment (income) expense, net, consists of the following components:
		Three Months Ended
	(In thousands)	August 31,			August 31,
		2013			2012
	Interest (income)	$	(1,503	)	$	(2,295	)
	(Gain) on sale of marketable securities		(2,197	)		(4,584	)
	Other-than-temporary impairment on securities		51			113
	Dividend (income)		(245	)		(208	)
	Investment (income) expense, net	$	(3,894	)	$	(6,974	)

Other_Expense_Income_Net

Other Expense (Income), Net	3 Months Ended
	Aug. 31, 2013
Other Expense (Income), Net	NOTE 6 — OTHER EXPENSE (INCOME), NET
	Other expense (income), net, consists of the following components:
		Three Months Ended
	(In thousands)	August 31,			August 31,
		2013			2012
	Royalty expense (income), net	$	318		$	(294	)
	Loss on Kemrock conversion option		—			8,183
	(Income) loss related to unconsolidated equity affiliates		(752	)		31,533
	Other expense (income), net	$	(434	)	$	39,422

Pension_Plans

Pension Plans	3 Months Ended
	Aug. 31, 2013
Pension Plans	NOTE 7 — PENSION PLANS
	We offer defined benefit pension plans, defined contribution pension plans, as well as several unfunded health care benefit plans primarily for certain of our retired employees. The following tables provide the retirement-related benefit plans’ impact on income before income taxes for the three month periods ended August 31, 2013:
		U.S. Plans						Non-U.S. Plans
		Three Months Ended						Three Months Ended
	Pension Benefits	August 31,			August 31,			August 31,			August 31,
		2013			2012			2013			2012
		(In thousands)
	Service cost	$	6,764		$	6,488		$	1,109		$	1,050
	Interest cost		4,510			4,060			1,800			1,769
	Expected return on plan assets		(5,190	)		(4,358	)		(2,095	)		(1,846	)
	Amortization of:
	Prior service cost		83			87			1			2
	Net actuarial losses recognized		3,306			4,222			623			692
	Net Periodic Benefit Cost	$	9,473		$	10,499		$	1,438		$	1,667
		U.S. Plans						Non-U.S. Plans
		Three Months Ended						Three Months Ended
	Postretirement Benefits	August 31,			August 31,			August 31,			August 31,
		2013			2012			2013			2012
		(In thousands)
	Service cost	$	—		$	—		$	327		$	288
	Interest cost		81			88			317			289
	Amortization of:
	Prior service (credit)		(22	)		(22	)
	Net actuarial (gains) losses recognized		(29	)		4			133			114
	Net Periodic Benefit Cost	$	30		$	70		$	777		$	691
	We previously disclosed in our financial statements for the fiscal year ended May 31, 2013 that we expected to contribute approximately $27.4 million to our retirement plans in the U.S. and approximately $7.4 million to plans outside the U.S. during the current fiscal year. As of August 31, 2013, this has not changed.
	We have determined that our postretirement medical plan provides prescription drug benefits that will qualify for the federal subsidy provided by the Medicare Prescription Drug, Improvement and Modernization Act of 2003. For all groups of retirees, we have assumed that the subsidy will continue indefinitely.

Income_Taxes

Income Taxes	3 Months Ended
	Aug. 31, 2013
Income Taxes	NOTE 8 — INCOME TAXES
	The effective income tax rate was 27.4% for the three months ended August 31, 2013 compared to an effective income tax rate of 47.5% for the three months ended August 31, 2012.
	For the three months ended August 31, 2013 and August 31, 2012, the effective tax rates reflect variances from the 35% federal statutory rate primarily due to lower effective tax rates of certain of our foreign subsidiaries, the favorable impact of certain foreign operations on our U.S. taxes, the research and development tax credit, the benefit of the domestic manufacturing deduction and for the three months ended August 31, 2013, the impact of lower valuation allowances on foreign tax credit carryforwards. These favorable variances from the statutory tax rate were offset by the net impact of valuation allowances associated with certain foreign net operating losses, state and local income taxes, non-deductible business operating expenses, and for the three months ended August 31, 2012, the impact of increases to valuation allowances for both foreign tax credit carryfowards and loss carryforwards on our investment in Kemrock.
	Furthermore, for the three month period ended August 31, 2013, the effective tax rate includes a discrete benefit related to the recognition of a foreign deferred income tax asset resulting from the merger of certain foreign subsidiaries. This benefit was partially offset by the impact of the enactment of a Canadian tax law change, Canada Bill C-48, Technical Tax Amendments Act, 2012 (“Bill C-48”), which was effective as of June 26, 2013.
	As of August 31, 2013, we had unrecognized tax benefits of approximately $15.0 million, of which approximately $14.1 million would impact the effective tax rate, if recognized. We recognize interest and penalties related to unrecognized tax benefits in income tax expense. At August 31, 2013 the accrual for interest and penalties was $5.8 million. These amounts increased from the prior year balances primarily due to additions for prior year positions related to the retroactive impact of Bill C-48. Unrecognized tax benefits, including interest and penalties, have been classified as other long-term liabilities unless expected to be paid in one year. We do not anticipate any significant changes to the total unrecognized tax benefits within the next 12 months.
	We, or our subsidiaries, file income tax returns in the U.S. and in various state, local and foreign jurisdictions. During the year ended May 31, 2013 we settled U.S. federal examinations of fiscal years 2009 and 2010. During the first quarter of fiscal 2014 we settled a U.S. federal examination of fiscal year 2011 and were notified by the Internal Revenue Service that they will perform a limited scope examination of fiscal year 2012. In addition, with limited exceptions, we, or our subsidiaries, are generally subject to state and local or non-U.S. income tax examinations by tax authorities for the fiscal years 2006 through 2013.
	We are currently under examination, or have been notified of an upcoming tax examination, for various Non-U.S. and U.S. jurisdictions. Although it is possible that certain tax examinations could be resolved during the next 12 months, the timing and outcomes are uncertain.
	As of August 31, 2013, we have determined, based on the available evidence, that it is uncertain whether we will be able to recognize certain deferred tax assets. Therefore, we intend to maintain the tax valuation allowances recorded at August 31, 2013 for those deferred tax assets until sufficient positive evidence (for example, cumulative positive foreign earnings or additional foreign source income) exists to support their reversal. These valuation allowances relate to U.S. foreign tax credit carryforwards, capital loss carryforwards, unrealized losses on securities, certain foreign net operating losses and net foreign deferred tax assets.

Earnings_Per_Share

Earnings Per Share	3 Months Ended
	Aug. 31, 2013
Earnings Per Share	NOTE 9 — EARNINGS PER SHARE
	The following table sets forth the reconciliation of the numerator and denominator of basic and diluted earnings per share, as calculated using the two-class method, for the three month periods ended August 31, 2013 and 2012:
			Three Months Ended
			August 31,
	(In thousands, except per share amounts)		2013			2012
	Numerator for earnings per share:
	Net income attributable to RPM International Inc. stockholders		$	103,098		$	33,913
	Less: Allocation of earnings and dividends to participating securities			(2,285	)		(642	)
	Net income available to common shareholders — basic			100,813			33,271
	Add: Undistributed earnings reallocated to unvested shareholders			12			1
	Net income available to common shareholders — diluted		$	100,825		$	33,272
	Denominator for basic and diluted earnings per share:
	Basic weighted average common shares			129,344			128,805
	Average diluted options			950			765
	Total shares for diluted earnings per share			130,294			129,570
	Earnings Per Share of Common Stock Attributable to RPM International Inc. Stockholders:
	Basic		$	0.78		$	0.26
	Diluted (1)		$	0.77		$	0.26
	-1	For the quarters ended August 31, 2013 and 2012, approximately 3,097,000 and 2,954,000 shares of stock, respectively, granted under stock-based compensation plans were excluded from the calculation of diluted earnings per share, as the effect would have been anti-dilutive.

Inventories

Inventories	3 Months Ended
	Aug. 31, 2013
Inventories	NOTE 10 — INVENTORIES
	Inventories were composed of the following major classes:
		August 31, 2013		May 31, 2013
		(In thousands)
	Raw material and supplies	$	190,910	$	185,590
	Finished goods		381,238		363,090
	Total Inventory	$	572,148	$	548,680

Restructuring

Restructuring	3 Months Ended
	Aug. 31, 2013
Restructuring	NOTE 11 — RESTRUCTURING
	We record restructuring charges associated with management-approved restructuring plans to either reorganize one or more of our business segments, or to remove duplicative headcount and infrastructure associated with our businesses. Restructuring charges can include severance costs to eliminate a specified number of employees, infrastructure charges to vacate facilities and consolidate operations, and contract cancellation costs. Restructuring charges are recorded based upon planned employee termination dates and site closure and consolidation plans. The timing of associated cash payments is dependent upon the type of restructuring charge and can extend over a multi-year period. We record the short-term portion of our restructuring liability in Other accrued liabilities and the long-term portion, if any, in Other long-term liabilities in our Consolidated Balance Sheets.
	Fiscal 2013 Plans
	In May 2013, we approved a restructuring plan for one of our consumer operating segments designed to eliminate duplicative processes and overhead and to exit certain processes and product lines. This restructuring plan allows management to refocus its attention on faster growing brands within the consumer operating segment. In connection with this plan, we recorded aggregate charges of approximately $15.6 million, of which approximately $8.2 million relates to the elimination of 133 positions and approximately $7.4 million results from the shutdown of 2 manufacturing facilities. These actions are expected to be completed during the first seven months of fiscal 2014. In addition, there were approximately $3.9 million of inventory markdowns, which are reflected in Cost of Sales in our Consolidated Statements of Income.
	Additionally, one of our industrial operating businesses adopted a restructuring plan designed to simplify business processes, accelerate innovation and deliver better results for customers, employees and stockholders. We estimate that this plan will eliminate approximately 34 positions and severance payments will be made generally through the end of fiscal 2014. In connection with the plan, we recorded aggregate charges of approximately $4.5 million, all of which relates to workforce reductions.
	The following table includes the changes in our accrued restructuring balances:
	(In thousands)	Long-Lived		Employee			Site		Total
		Asset		Severance			Preparation
		Charges					and
							Equipment
							Relocation
	Balance at May 31, 2013	$	4,729	$	12,656		$	397	$	17,782
	Charge to expense		—		128			—		128
	Cash payments		—		(1,416	)		—		(1,416	)
	Noncash and foreign exchange impacts		123		165			10		298
	Balance at August 31, 2013	$	4,852	$	11,533		$	407	$	16,792

Marketable_Securities

Marketable Securities	3 Months Ended
	Aug. 31, 2013
Marketable Securities	NOTE 12 — MARKETABLE SECURITIES
	The following tables summarize marketable securities held at August 31, 2013 and May 31, 2013 by asset type:
		Available-For-Sale Securities
	(In thousands)	Amortized		Gross			Gross			Fair Value
		Cost		Unrealized			Unrealized			(Net
				Gains			Losses			Carrying
										Amount)
	August 31, 2013
	Equity securities:
	Stocks — foreign	$	1,090	$	367		$	(47	)	$	1,410
	Stocks — domestic		30,931		4,749			(488	)		35,192
	Mutual funds — foreign		26,348		2,018			(148	)		28,218
	Mutual funds — domestic		27,835		233			(1,340	)		26,728
	Total equity securities		86,204		7,367			(2,023	)		91,548
	Fixed maturity:
	U.S. treasury and other government		20,386		166			(341	)		20,211
	Corporate bonds		1,714		192			(1	)		1,905
	Foreign bonds		37		3			—			40
	Mortgage-backed securities		88		58			—			146
	Total fixed maturity securities		22,225		419			(342	)		22,302
	Total	$	108,429	$	7,786		$	(2,365	)	$	113,850
		Available-For-Sale Securities
	(In thousands)	Amortized		Gross			Gross			Fair Value
		Cost		Unrealized			Unrealized			(Net
				Gains			Losses			Carrying
										Amount)
	May 31, 2013
	Equity securities:
	Stocks — foreign	$	1,090	$	244		$	—		$	1,334
	Stocks — domestic		24,492		5,265			(392	)		29,365
	Mutual funds — foreign		18,328		1,901			(7	)		20,222
	Mutual funds — domestic		39,184		679			(492	)		39,371
	Total equity securities		83,094		8,089			(891	)		90,292
	Fixed maturity:
	U.S. treasury and other government		20,528		247			(139	)		20,636
	Corporate bonds		1,724		244			—			1,968
	Foreign bonds		37		4			—			41
	Mortgage-backed securities		100		60			(4	)		156
	Total fixed maturity securities		22,389		555			(143	)		22,801
	Total	$	105,483	$	8,644		$	(1,034	)	$	113,093
	Marketable securities, included in other current and long-term assets totaling $52.0 million and $61.9 million at August 31, 2013, respectively, and included in other current and long-term assets totaling $49.1 million and $64.0 million at May 31, 2013, respectively, are composed of available-for-sale securities and are reported at fair value. We carry a portion of our marketable securities portfolio in long-term assets since they are generally held for the settlement of our general and product liability insurance claims processed through our wholly owned captive insurance subsidiaries.
	Marketable securities are composed of available-for-sale securities and are reported at fair value. Realized gains and losses on sales of investments are recognized in net income on the specific identification basis. Changes in the fair values of securities that are considered temporary are recorded as unrealized gains and losses, net of applicable taxes, in accumulated other comprehensive income (loss) within stockholders’ equity. Other-than-temporary declines in market value from original cost are reflected in operating income in the period in which the unrealized losses are deemed other than temporary. In order to determine whether other-than-temporary declines in market value have occurred, the duration of the decline in value and our ability to hold the investment are considered in conjunction with an evaluation of the strength of the underlying collateral and the extent to which the investment’s amortized cost or cost, as appropriate, exceeds its related market value.
	Gross gains realized on sales of investments were $2.2 million for the quarter ended August 31, 2013. Gross gains and losses realized on sales of investments were $5.0 million and $0.4 million, respectively, for the quarter ended August 31, 2012. During the three months ended August 31, 2013 and 2012, we recognized losses of approximately $0.1 million for securities deemed to have other-than-temporary impairments. These amounts are included in investment expense (income), net in the Consolidated Statements of Income.
	Summarized below are the securities we held at August 31, 2013 and May 31, 2013 that were in an unrealized loss position and that were included in accumulated other comprehensive income, aggregated by the length of time the investments had been in that position:
		August 31, 2013					May 31, 2013
	(In thousands)	Fair Value		Gross			Fair Value			Gross
				Unrealized						Unrealized
				Losses						Losses
	Total investments with unrealized losses	$	48,861	$	(2,365	)	$	36,582		$	(1,034	)
	Unrealized losses with a loss position for less than 12 months		46,046		(2,277	)		36,327			(956	)
	Unrealized losses with a loss position for more than 12 months		2,815		(88	)		255			(78	)
	We have reviewed all of the securities included in the table above and have concluded that we have the ability and intent to hold these investments until their cost can be recovered, based upon the severity and duration of the decline. Therefore, we did not recognize any other-than-temporary impairment losses on these investments. Unrealized losses at August 31, 2013 were generally related to the lower levels of volatility in valuations over the last several months for a portion of our portfolio of investments in marketable securities. The unrealized losses generally relate to investments whose fair values at August 31, 2013 were less than 15% below their original cost or have been in a loss position for less than six consecutive months. From time to time, we may experience significant volatility in general economic and market conditions. If we were to experience unrealized losses that were to continue for longer periods of time, or arise to more significant levels of unrealized losses within our portfolio of investments in marketable securities in the future, we may recognize additional other-than-temporary impairment losses. Such potential losses could have a material impact on our results of operations in any given reporting period. As such, we continue to closely evaluate the status of our investments and our ability and intent to hold these investments.
	The net carrying values of debt securities at August 31, 2013, by contractual maturity, are shown below. Expected maturities may differ from contractual maturities because the issuers of the securities may have the right to prepay obligations without prepayment penalties.
	(In thousands)	Amortized		Fair
		Cost		Value
	Due:
	Less than one year	$	3,081	$	3,093
	One year through five years		13,043		13,100
	Six years through ten years		4,439		4,322
	After ten years		1,662		1,787
		$	22,225	$	22,302

Fair_Value_Measurements

Fair Value Measurements	3 Months Ended
	Aug. 31, 2013
Fair Value Measurements	NOTE 13 — FAIR VALUE MEASUREMENTS
	Financial instruments recorded on the balance sheet include cash and cash equivalents, trade accounts receivable, marketable securities, notes and accounts payable, and debt.
	An allowance for anticipated uncollectible trade receivable amounts is established using a combination of specifically identified accounts to be reserved, and a reserve covering trends in collectibility. These estimates are based on an analysis of trends in collectability and past experience, but are primarily made up of individual account balances identified as doubtful based on specific facts and conditions. Receivable losses are charged against the allowance when we confirm uncollectibility.
	All derivative instruments are recognized on our Consolidated Balance Sheet and measured at fair value. Changes in the fair values of derivative instruments that do not qualify as hedges and/or any ineffective portion of hedges are recognized as a gain or (loss) in our Consolidated Statement of Income in the current period. Changes in the fair value of derivative instruments used effectively as cash flow hedges are recognized in other comprehensive income (loss), along with the change in the value of the hedged item. We do not hold or issue derivative instruments for speculative purposes.
	The valuation techniques utilized for establishing the fair values of assets and liabilities are based on observable and unobservable inputs. Observable inputs reflect readily obtainable data from independent sources, while unobservable inputs reflect management’s market assumptions. The fair value hierarchy has three levels based on the reliability of the inputs used to determine fair value, as follows:
	Level 1 Inputs — Quoted prices for identical instruments in active markets.
	Level 2 Inputs — Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations whose inputs are observable or whose significant value drivers are observable.
	Level 3 Inputs — Instruments with primarily unobservable value drivers.
	The following tables present our assets and liabilities that are measured at fair value on a recurring basis and are categorized using the fair value hierarchy.
	(In thousands)	Quoted Prices in		Significant			Significant			Fair Value at
		Active Markets		Other			Unobservable			August 31, 2013
		for Identical		Observable			Inputs (Level 3)
		Assets (Level 1)		Inputs (Level 2)
	U.S. Treasury and other government	$	—	$	20,211		$	—		$	20,211
	Foreign bonds				40						40
	Mortgage-backed securities				146						146
	Corporate bonds				1,905						1,905
	Stocks — foreign		1,410								1,410
	Stocks — domestic		35,192								35,192
	Mutual funds — foreign				28,218						28,218
	Mutual funds — domestic				26,728						26,728
	Foreign currency forward contract				1,687						1,687
	Cross-currency swap				(12,708	)					(12,708	)
	Contingent consideration				—			(68,050	)		(68,050	)
	Total	$	36,602	$	66,227		$	(68,050	)	$	34,779
	(In thousands)	Quoted Prices in		Significant			Significant			Fair Value at
		Active Markets		Other			Unobservable			May 31, 2013
		for Identical		Observable			Inputs (Level 3)
		Assets (Level 1)		Inputs (Level 2)
	U.S. Treasury and other government	$	—	$	20,636		$	—		$	20,636
	Foreign bonds				41						41
	Mortgage-backed securities				156						156
	Corporate bonds				1,968						1,968
	Stocks — foreign		1,334								1,334
	Stocks — domestic		29,365								29,365
	Mutual funds — foreign				20,222						20,222
	Mutual funds — domestic				39,371						39,371
	Foreign currency forward contract				(4,751	)					(4,751	)
	Cross-currency swap				(10,048	)					(10,048	)
	Contingent consideration							(64,500	)		(64,500	)
	Total	$	30,699	$	67,595		$	(64,500	)	$	33,794
	Our marketable securities are composed of mainly available-for-sale securities, and are valued using a market approach. The availability of inputs observable in the market varies from instrument to instrument and depends on a variety of factors including the type of instrument, whether the instrument is actively traded, and other characteristics particular to the transaction. For most of our financial instruments, pricing inputs are readily observable in the market, the valuation methodology used is widely accepted by market participants, and the valuation does not require significant management discretion. For other financial instruments, pricing inputs are less observable in the market and may require management judgment.
	Our cross-currency swap is a liability that has a fair value of $12.7 million at August 31, 2013, that was originally designed to fix our interest and principal payments in euros for the life of our unsecured 6.70% senior notes due November 1, 2015, which resulted in an effective euro fixed-rate borrowing of 5.31%. The basis for determining the rates for this swap included three legs at the inception of the agreement: the U.S. dollar (USD) fixed rate to a USD floating rate; the euro floating to euro fixed rate; and the dollar to euro basis fixed rate at inception. Therefore, we essentially exchanged fixed payments denominated in USD for fixed payments denominated in euros, paying fixed euros at 5.31% and receiving fixed USD at 6.70%. The ultimate payments are based on the notional principal amounts of $150 million and approximately 125 million euros. There will be an exchange of the notional amounts at maturity. The rates included in this swap are based upon observable market data, but are not quoted market prices, and therefore, the cross-currency swap is considered a Level 2 liability on the fair value hierarchy. Additionally, this cross-currency swap has been designated as a hedging instrument, and is classified as other long-term liabilities in our Consolidated Balance Sheets.
	At August 31, 2013, we had a foreign currency forward contract with a fair value of approximately $1.7 million, which is classified in other current assets in our Consolidated Balance Sheets. At May 31, 2013, we had a foreign currency forward contract with a fair value of $4.8 million, which is classified as other accrued liabilities in our Consolidated Balance Sheets. Our foreign currency forward contract, which has not been designated as a hedge, was designed to reduce our exposure to the changes in the cash flows of intercompany foreign-currency-denominated loans related to changes in foreign currency exchange rates by fixing the functional currency cash flows. The foreign exchange rates included in the forward contract are based upon observable market data, but are not quoted market prices, and therefore, the forward currency forward contract is considered a Level 2 liability on the fair value hierarchy.
	The contingent consideration represents the estimated fair value of the additional variable cash consideration payable in connection with recent acquisitions that is contingent upon the achievement of certain performance milestones. We estimated the fair value using expected future cash flows over the period in which the obligation is expected to be settled, and applied a discount rate that appropriately captures a market participant’s view of the risk associated with the obligation.
	The carrying value of our current financial instruments, which include cash and cash equivalents, marketable securities, trade accounts receivable, accounts payable and short-term debt approximates fair value because of the short-term maturity of these financial instruments. At August 31, 2013 and May 31, 2013, the fair value of our long-term debt was estimated using active market quotes, based on our current incremental borrowing rates for similar types of borrowing arrangements, which are considered to be Level 2 inputs. Based on the analysis performed, the fair value and the carrying value of our financial instruments and long-term debt as of August 31, 2013 and May 31, 2013 are as follows:
		At August 31, 2013
	(In thousands)	Carrying		Fair Value
		Value
	Cash and cash equivalents	$	204,903	$	204,903
	Marketable equity securities		91,548		91,548
	Marketable debt securities		22,302		22,302
	Long-term debt, including current portion		1,424,144		1,504,714
		At May 31, 2013
	(In thousands)	Carrying		Fair Value
		Value
	Cash and cash equivalents	$	343,554	$	343,554
	Marketable equity securities		90,292		90,292
	Marketable debt securities		22,801		22,801
	Long-term debt, including current portion		1,373,697		1,501,850

Reorganization_Proceedings_of_

Reorganization Proceedings of Certain Subsidiaries	3 Months Ended
	Aug. 31, 2013
Reorganization Proceedings of Certain Subsidiaries	NOTE 14 — REORGANIZATION PROCEEDINGS OF CERTAIN SUBSIDIARIES
	General — Prior to May 31, 2010, Bondex and SPHC were defendants in various asbestos-related bodily injury lawsuits filed in various state courts. These cases generally sought unspecified damages for asbestos-related diseases based on alleged exposures to asbestos-containing products.
	On May 31, 2010, Bondex and its parent, SPHC, filed voluntary petitions for relief under Chapter 11 of the Bankruptcy Code in the U.S. Bankruptcy Court for the District of Delaware. SPHC is also the parent company for various operating companies that are not part of the reorganization filing, including Chemical Specialties Manufacturing Corp.; Day-Glo Color Corp.; Dryvit Holdings, Inc.; Guardian Protection Products Inc.; Kop-Coat Inc.; TCI, Inc. and RPM Wood Finishes Group, Inc. SPHC and Bondex (the “filing entities”) took this action in an effort to permanently and comprehensively resolve all pending and future asbestos-related liability claims associated with Bondex and SPHC-related products. As a result of the filing, all Bondex and SPHC asbestos personal injury lawsuits have been stayed due to the imposition of an automatic stay applicable in bankruptcy cases, with the exception of the cases referenced in Note 3 with respect to which the stay was lifted. In addition, at the request of SPHC and Bondex, the bankruptcy court has entered orders staying all claims against RPM International Inc. and its affiliates that are derivative of the asbestos claims against SPHC and Bondex.
	Through the Chapter 11 proceedings, the filing entities are seeking to formulate a consensual plan of reorganization pursuant to Section 524(g) of the Bankruptcy Code. That contemplated plan of reorganization would establish a trust to which all present and future asbestos claims against the debtors would be channeled, and which would provide compensation to the asbestos claimants based upon factors set forth in trust distribution procedures provided for by the plan of reorganization. We would hope to have any channeling order issued by the bankruptcy court in connection with such a plan of reorganization also protect ourselves as well as other non-filing affiliates of the debtors, so that all future SPHC-related and Bondex-related asbestos claims must proceed against the trust and cannot be asserted against us or other non-filing affiliates. The ultimate ability to achieve such a consensual plan of reorganization on such terms, however, depends on numerous factors, and no assurance can be provided that such a plan of reorganization with these terms will, in fact, be achieved.
	In January 2013, a hearing to estimate the aggregate current and future asbestos liabilities of the filing entities was conducted before Judge Judith K. Fitzgerald in the United States Bankruptcy Court for the District of Delaware (the “Bankruptcy Court”). In May 2013, the Bankruptcy Court issued an opinion estimating the current and future asbestos claims associated with Bondex and SPHC at approximately $1.17 billion. The estimation hearing represents one step in the legal process in helping to determine the appropriate amount of funding for a 524(g) asbestos trust. Bondex and SPHC firmly believe that the ruling substantially overstates the amount of their liability and is not supported by the facts or the law. The debtors have filed an appeal of the decision and are seeking certification of the appeal directly to the United States Court of Appeals for the Third Circuit, thereby bypassing review by the United States District Court for the District of Delaware. We have also separately filed an appeal. The asbestos claimants and the future claims representative have moved to dismiss the appeals, arguing that the estimation order is not a final, appealable order. Bondex, SPHC and we believe that the order is final and appealable, and that, even if it were not, the appeal should be treated as a motion to appeal, which should be granted. Assuming that the motion to dismiss the appeal is not granted, it is anticipated that the appeal process could take an additional two to three years. That time period could be shorter if the appeal is certified to and heard directly by the United States Court of Appeals for the Third Circuit.
	Prior to the bankruptcy filing, the filing entities had litigated and, on many occasions, settled asbestos-related products liability claims brought against them. The debtors paid $92.6 million during the year ended May 31, 2010, prior to the bankruptcy filing, in connection with the litigation and settlement of asbestos claims, $42.6 million of which consisted of defense costs. With the exception of the appeal bonds described in Note 3, no claims have been paid since the bankruptcy filing and it is not contemplated that any claims will be paid until a plan of reorganization is confirmed and an asbestos trust is established and operating.
	Prior to the Chapter 11 bankruptcy filing, we recorded asbestos-related contingent liabilities that included estimations of future costs. Such estimates by their nature are subject to many uncertainties that may change over time, including (i) the ultimate number of claims filed; (ii) the amounts required to resolve both currently known and future unknown claims; (iii) the amount of insurance, if any, available to cover such claims, including the outcome of coverage litigation against the filing entities’ third-party insurers; (iv) future earnings and cash flow of the filing entities; (v) the impact of bankruptcies of other companies whose share of liability may be imposed on the filing entities under certain state liability laws; (vi) the unpredictable aspects of the litigation process including a changing trial docket and the jurisdictions in which trials are scheduled; (vii) the outcome of any such trials, including potential judgments or jury verdicts, as a result of the strategy of Bondex and SPHC to take selective cases to verdict; (viii) the lack of specific information in many cases concerning exposure to products for which Bondex, SPHC, or another of our subsidiaries is allegedly responsible, and the claimants’ alleged diseases resulting from such exposure; (ix) potential changes in applicable federal and/or state tort liability law; and (x) the potential impact of various proposed structured settlement transactions. All these factors may have a material effect upon future asbestos-related liability estimates.
	As a result of their bankruptcy filing, SPHC and Bondex are precluded from paying dividends to shareholders and from making payments on any pre-bankruptcy filing accounts or notes payable that are due and owing to any other entity within the RPM group of companies (the “Pre-Petition Intercompany Payables”) or other pre-petition creditors during the pendency of the bankruptcy case, without the Bankruptcy Court’s approval. Moreover, no assurances can be given that any of the Pre-Petition Intercompany Payables will ever be paid or otherwise satisfied.
	When SPHC emerges from the jurisdiction of the Bankruptcy Court, the subsequent accounting will be determined based upon the applicable circumstances and facts at such time, including the terms of any plan of reorganization.
	SPHC has assessed its liquidity position as a result of the bankruptcy filing and believes that it can continue to fund its and its subsidiaries’ operating activities and meet its debt and capital requirements for the foreseeable future.
	Historical Asbestos Liability Reserve — In fiscal 2006, management retained Crawford & Winiarski (“C&W”), an independent, third-party consulting firm with expertise in the area of asbestos valuation work, to assist it in calculating an estimate of Bondex’s liability for unasserted-potential-future-asbestos-related claims. C&W’s methodology to project Bondex’s liability for unasserted-potential-future-asbestos-related claims included an analysis of: (a) a widely accepted forecast of the population likely to have been exposed to asbestos; (b) epidemiological studies estimating the number of people likely to develop asbestos-related diseases; (c) the historical rate at which mesothelioma incidences resulted in the payment of claims by Bondex; (d) the historical settlement averages to value the projected number of future compensable mesothelioma claims; (e) the historical ratio of mesothelioma-related indemnity payments to non-mesothelioma indemnity payments; and (f) the historical defense costs and their relationship with total indemnity payments. Based upon the results of this analysis, Bondex recorded an accrued liability for asbestos claims through 2016 as of May 31, 2006 of $421.3 million. This amount was calculated on a pretax basis and was not discounted for the time value of money.
	During the fiscal year ended May 31, 2008, the ten-year asbestos liability established as of May 31, 2006 was reviewed and evaluated. As part of that process, the credibility of epidemiological studies of Bondex’s mesothelioma claims, first introduced to management by C&W some two-and-one-half years earlier, was validated. At the core of the evaluation process, and the basis of C&W’s actuarial work on behalf of Bondex, is the Nicholson Study. The Nicholson Study is the most widely recognized reference in bankruptcy trust valuations, global settlement negotiations and the Congressional Budget Office’s work done on the proposed FAIR Act in 2006. Based on our ongoing comparison of the Nicholson Study projections and Bondex’s specific actual experience, which at that time continued to bear an extremely close correlation to the study’s projections, the asbestos liability projection was extended out to the year 2028. C&W assisted in calculating an estimate of our liability for unasserted-potential-future-asbestos-related claims out to 2028. C&W projected that the cost of extending the asbestos liability to 2028, coupled with an updated evaluation of Bondex’s current known claims to reflect its most recent actual experience, would be $288.1 million. Therefore, management added $288.1 million to the existing asbestos liability, which brought Bondex’s total asbestos-related balance sheet liabilities at May 31, 2008 to $559.7 million. On May 30, 2010, the day prior to the bankruptcy filing, Bondex had recorded an asbestos related product liability of $397.7 million.
	As noted above, however, the Bankruptcy Court has now estimated the present and future asbestos-related liabilities of Bondex and SPHC at $1.17 billion, and that determination is the subject of pending appeals.

Contingencies_and_Other_Accrue

Contingencies and Other Accrued Losses	3 Months Ended
	Aug. 31, 2013
Contingencies and Other Accrued Losses	NOTE 15 — CONTINGENCIES AND OTHER ACCRUED LOSSES
	We provide, through our wholly owned insurance subsidiaries, certain insurance coverage, primarily product liability coverage, to our other subsidiaries. Excess coverage is provided by third-party insurers. Our reserves provide for these potential losses as well as other uninsured claims. Product liability reserves are established based upon actuarial calculations of potential liability using industry experience, actual historical experience and actuarial assumptions developed for similar types of product liability claims, including development factors and lag times. While it is reasonably possible that excess liabilities, if they were to occur, could be material to operating results in any given quarter or year of their recognition, we do not believe that it is reasonably possible that excess liabilities would have a material adverse effect on our long-term results of operations, liquidity or consolidated financial position.
	We also offer warranty programs at several of our industrial businesses and have established a product warranty liability. We review this liability for adequacy on a quarterly basis and adjust it as necessary. The primary factors that could affect this liability may include changes in the historical system performance rate as well as the costs of replacement. Provision for estimated warranty costs is recorded at the time of sale and periodically adjusted, as required, to reflect actual experience. It is probable that we will incur future losses related to warranty claims we have received but that have not been fully investigated and related to claims not yet received. While our warranty liability represents our best estimate at August 31, 2013, we can provide no assurances that we will not experience material claims in the future or that we will not incur significant costs to resolve such claims beyond the amounts accrued or beyond what we may recover from our suppliers. Product warranty expense is recorded within selling, general and administrative expense.
	The following table includes the changes in our accrued warranty balances:
			Quarter Ended
			August 31,
	(In thousands)		2013			2012
	Beginning Balance		$	9,330		$	14,751
	Deductions (1)			(4,796	)		(3,905	)
	Provision charged to SG&A expense			5,308			3,681
	Ending Balance		$	9,842		$	14,527
	-1	Primarily claims paid during the year.
	In addition, like other companies participating in similar lines of business, some of our subsidiaries are involved in several proceedings relating to environmental matters. It is our policy to accrue remediation costs when it is probable that such efforts will be required and the related costs can be reasonably estimated. These liabilities are undiscounted and are not material to our financial statements during any of the periods presented.
	As previously disclosed, we recorded a $65.1 million accrual during the year ended May 31, 2013 associated with settlement discussions with the U.S. Department of Justice (the “DOJ”) and the U.S. General Services Administration (the “GSA”) Office of Inspector General aimed at resolving an existing investigation. Since first receiving a broad request for documents from the GSA in March 2011, we cooperated with that investigation, which involved our compliance with certain pricing terms and conditions of our GSA Multiple Award Schedule contracts under which the roofing division of our Building Solutions Group sold products and services to the federal government. A substantial majority of the transactions as to which potential compliance issues were raised took place during the period from 2002 to 2008. In August 2013, we entered into a final agreement with the DOJ and the GSA Office of Inspector General regarding this matter. During the quarter ended August 31, 2013, we paid the GSA Office of Inspector General $61.9 million, and we expect to pay approximately $3.2 million more in legal fees and other related costs arising out of this investigation. The accrual for this contingency represents our assessment of the amount of probable loss that may result from this matter. In assessing our probable loss, we have considered the potentially disputed amounts under the relevant contracts, together with our understanding of policies for resolving such matters. The actual amount of our loss under the terms of any settlement may vary from the amount of the accrual. The accrual for this contingency is classified in other accrued liabilities in our Consolidated Balance Sheets.

Stock_Repurchase_Program

Stock Repurchase Program	3 Months Ended
	Aug. 31, 2013
Stock Repurchase Program	NOTE 16 — STOCK REPURCHASE PROGRAM
	On January 8, 2008, we announced our authorization of a stock repurchase program under which we may repurchase shares of RPM International Inc. common stock at management’s discretion for general corporate purposes. Our current intent is to limit our repurchases only to amounts required to offset dilution created by stock issued in connection with our equity-based compensation plans, or approximately one to two million shares per year. As a result of this authorization, we may repurchase shares from time to time in the open market or in private transactions at various times and in amounts and for prices that our management deems appropriate, subject to insider trading rules and other securities law restrictions. The timing of our purchases will depend upon prevailing market conditions, alternative uses of capital and other factors. We may limit or terminate the repurchase program at any time. During the three months ended August 31, 2013, we did not repurchase any shares of our common stock under this program.

Equity

Equity	3 Months Ended
	Aug. 31, 2013
Equity	NOTE 17 — EQUITY
	The following tables illustrate the components of total equity and comprehensive income for the three months ended August 31, 2013 and 2012:
	(In thousands)	Total RPM			Noncontrolling			Total Equity
		International			Interest
		Inc. Equity
	Total equity at May 31, 2013	$	1,200,858		$	154,075		$	1,354,933
	Net income		103,098			3,791			106,889
	Other Comprehensive Income:
	Foreign currency translation adjustments		(17,071	)		3,657			(13,414	)
	Pension and other postretirement benefit liability adjustments, net of tax		2,761			163			2,924
	Unrealized (loss) on securities, net of tax		(1,432	)		(7	)		(1,439	)
	Unrealized gain on derivatives, net of tax		86			23			109
	Total Other Comprehensive Income, net of tax		(15,656	)		3,836			(11,820	)
	Comprehensive Income		87,442			7,627			95,069
	Dividends paid		(29,836	)					(29,836	)
	Other noncontrolling interest activity		(341	)		341			—
	Stock option exercises, net		2,401						2,401
	Stock based compensation expense		709						709
	Restricted awards, net		451						451
	Total Equity at August 31, 2013	$	1,261,684		$	162,043		$	1,423,727
	(In thousands)	Total RPM			Noncontrolling			Total Equity
		International			Interest
		Inc. Equity
	Total equity at May 31, 2012	$	1,183,656		$	130,327		$	1,313,983
	Net income		33,913			3,954			37,867
	Other Comprehensive Income:
	Foreign currency translation adjustments		28,664			10,566			39,230
	Pension and other postretirement benefit liability adjustments, net of tax		1,534			(328	)		1,206
	Unrealized gain (loss) on securities, net of tax		825			(1,177	)		(352	)
	Unrealized gain on derivatives, net of tax		169			18			187
	Total Other Comprehensive Income, net of tax		31,192			9,079			40,271
	Comprehensive Income		65,105			13,033			78,138
	Dividends paid		(28,281	)					(28,281	)
	Other noncontrolling interest activity		1,284			—			1,284
	Stock option exercises, net		603						603
	Stock based compensation expense		588						588
	Restricted awards, net		3,285						3,285
	Total Equity at August 31, 2012	$	1,226,240		$	143,360		$	1,369,600

Segment_Information

Segment Information	3 Months Ended
	Aug. 31, 2013
Segment Information	NOTE 18 — SEGMENT INFORMATION
	We operate a portfolio of businesses and product lines that manufacture and sell a variety of specialty paints, protective coatings and roofing systems, sealants and adhesives. We manage our portfolio by organizing our businesses and product lines into two reportable segments: the industrial reportable segment and the consumer reportable segment. Within each reportable segment, we aggregate several operating segments that consist of individual groups of companies and product lines, which generally address common markets, share similar economic characteristics, utilize similar technologies and can share manufacturing or distribution capabilities. Our seven operating segments represent components of our business for which separate financial information is available that is utilized on a regular basis by our chief executive officer in determining how to allocate the assets of the company and evaluate performance. These seven operating segments are each managed by an operating segment manager, who is responsible for the day-to-day operating decisions and performance evaluation of the operating segment’s underlying businesses.
	Our industrial reportable segment products are sold throughout North America and also account for the majority of our international sales. Our industrial product lines are sold directly to contractors, distributors and end-users, such as industrial manufacturing facilities, public institutions and other commercial customers. This reportable segment comprises four separate operating segments — Tremco Group, Tremco illbruck Group, Performance Coatings Group and RPM2-Industrial Group. Products and services within this reportable segment include construction chemicals; roofing systems; weatherproofing and other sealants; polymer flooring; edible coatings and specialty glazes for pharmaceutical, cosmetic and food industries; and other specialty chemicals.
	Our consumer reportable segment manufactures and markets professional use and do-it-yourself (“DIY”) products for a variety of mainly consumer applications, including home improvement and personal leisure activities. Our consumer segment’s major manufacturing and distribution operations are located primarily in North America, along with a few locations in Europe. Consumer segment products are primarily sold directly to mass merchandisers, home improvement centers, hardware stores, paint stores, craft shops, cosmetic companies and to other smaller customers through distributors. This reportable segment comprises three operating segments — DAP Group, RPM2-Consumer Group and Rust-Oleum Group. Products within this reportable segment include specialty, hobby and professional paints; nail care enamels; caulks; adhesives; silicone sealants and wood stains.
	In addition to our two reportable segments, there is a category of certain business activities and expenses, referred to as corporate/other, that does not constitute an operating segment. This category includes our corporate headquarters and related administrative expenses, results of our captive insurance companies, gains or losses on the sales of certain assets and other expenses not directly associated with either reportable segment. Assets related to the corporate/other category consist primarily of investments, prepaid expenses and headquarters’ property and equipment. These corporate and other assets and expenses reconcile reportable segment data to total consolidated income before income taxes and identifiable assets.
	We reflect income from our joint ventures on the equity method, and receive royalties from our licensees.
	The following tables reflect the results of our reportable segments consistent with our management philosophy, and represent the information we utilize, in conjunction with various strategic, operational and other financial performance criteria, in evaluating the performance of our portfolio of businesses.
		Three Months Ended
		August 31,			August 31,
		2013			2012
		(In thousands)
	Net Sales
	Industrial Segment	$	731,226		$	703,335
	Consumer Segment		433,448			343,379
	Consolidated	$	1,164,674		$	1,046,714
	Income (Loss) Before Income Taxes
	Industrial Segment	$	97,581		$	74,304
	Consumer Segment		82,717			58,788
	Corporate/Other		(33,082	)		(61,030	)
	Consolidated	$	147,216		$	72,062
		August 31,			May 31,
		2013			2013
	Identifiable Assets
	Industrial Segment	$	2,335,594		$	2,461,163
	Consumer Segment		1,644,161			1,584,336
	Corporate/Other		83,371			70,027
	Consolidated	$	4,063,126		$	4,115,526

Investment_Income_Expense_Net_

Investment (Income) Expense, Net (Tables)	3 Months Ended
	Aug. 31, 2013
Investment (Income) Expenses, Net	Investment (income) expense, net, consists of the following components:
		Three Months Ended
	(In thousands)	August 31,			August 31,
		2013			2012
	Interest (income)	$	(1,503	)	$	(2,295	)
	(Gain) on sale of marketable securities		(2,197	)		(4,584	)
	Other-than-temporary impairment on securities		51			113
	Dividend (income)		(245	)		(208	)
	Investment (income) expense, net	$	(3,894	)	$	(6,974	)

Other_Expense_Income_Net_Table

Other Expense (Income), Net (Tables)	3 Months Ended
	Aug. 31, 2013
Other Expense (Income), Net	Other expense (income), net, consists of the following components:
		Three Months Ended
	(In thousands)	August 31,			August 31,
		2013			2012
	Royalty expense (income), net	$	318		$	(294	)
	Loss on Kemrock conversion option		—			8,183
	(Income) loss related to unconsolidated equity affiliates		(752	)		31,533
	Other expense (income), net	$	(434	)	$	39,422

Pension_Plans_Tables

Pension Plans (Tables)	3 Months Ended
	Aug. 31, 2013
Retirement-Related Benefit Plans' Impact on Income Before Income Taxes	The following tables provide the retirement-related benefit plans’ impact on income before income taxes for the three month periods ended August 31, 2013:
		U.S. Plans						Non-U.S. Plans
		Three Months Ended						Three Months Ended
	Pension Benefits	August 31,			August 31,			August 31,			August 31,
		2013			2012			2013			2012
		(In thousands)
	Service cost	$	6,764		$	6,488		$	1,109		$	1,050
	Interest cost		4,510			4,060			1,800			1,769
	Expected return on plan assets		(5,190	)		(4,358	)		(2,095	)		(1,846	)
	Amortization of:
	Prior service cost		83			87			1			2
	Net actuarial losses recognized		3,306			4,222			623			692
	Net Periodic Benefit Cost	$	9,473		$	10,499		$	1,438		$	1,667
		U.S. Plans						Non-U.S. Plans
		Three Months Ended						Three Months Ended
	Postretirement Benefits	August 31,			August 31,			August 31,			August 31,
		2013			2012			2013			2012
		(In thousands)
	Service cost	$	—		$	—		$	327		$	288
	Interest cost		81			88			317			289
	Amortization of:
	Prior service (credit)		(22	)		(22	)
	Net actuarial (gains) losses recognized		(29	)		4			133			114
	Net Periodic Benefit Cost	$	30		$	70		$	777		$	691

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	3 Months Ended
	Aug. 31, 2013
Reconciliation of Numerator and Denominator of Basic and Diluted Earnings Per Share Calculated using Two-Class Method	The following table sets forth the reconciliation of the numerator and denominator of basic and diluted earnings per share, as calculated using the two-class method, for the three month periods ended August 31, 2013 and 2012:
			Three Months Ended
			August 31,
	(In thousands, except per share amounts)		2013			2012
	Numerator for earnings per share:
	Net income attributable to RPM International Inc. stockholders		$	103,098		$	33,913
	Less: Allocation of earnings and dividends to participating securities			(2,285	)		(642	)
	Net income available to common shareholders — basic			100,813			33,271
	Add: Undistributed earnings reallocated to unvested shareholders			12			1
	Net income available to common shareholders — diluted		$	100,825		$	33,272
	Denominator for basic and diluted earnings per share:
	Basic weighted average common shares			129,344			128,805
	Average diluted options			950			765
	Total shares for diluted earnings per share			130,294			129,570
	Earnings Per Share of Common Stock Attributable to RPM International Inc. Stockholders:
	Basic		$	0.78		$	0.26
	Diluted (1)		$	0.77		$	0.26
	-1	For the quarters ended August 31, 2013 and 2012, approximately 3,097,000 and 2,954,000 shares of stock, respectively, granted under stock-based compensation plans were excluded from the calculation of diluted earnings per share, as the effect would have been anti-dilutive.

Inventories_Tables

Inventories (Tables)	3 Months Ended
	Aug. 31, 2013
Major Classes of Inventories	Inventories were composed of the following major classes:
		August 31, 2013		May 31, 2013
		(In thousands)
	Raw material and supplies	$	190,910	$	185,590
	Finished goods		381,238		363,090
	Total Inventory	$	572,148	$	548,680

Restructuring_Tables

Restructuring (Tables)	3 Months Ended
	Aug. 31, 2013
Changes in Accrued Restructuring Balances	The following table includes the changes in our accrued restructuring balances:
	(In thousands)	Long-Lived		Employee			Site		Total
		Asset		Severance			Preparation
		Charges					and
							Equipment
							Relocation
	Balance at May 31, 2013	$	4,729	$	12,656		$	397	$	17,782
	Charge to expense		—		128			—		128
	Cash payments		—		(1,416	)		—		(1,416	)
	Noncash and foreign exchange impacts		123		165			10		298
	Balance at August 31, 2013	$	4,852	$	11,533		$	407	$	16,792

Marketable_Securities_Tables

Marketable Securities (Tables)	3 Months Ended
	Aug. 31, 2013
Summary of Marketable Securities by Asset Type	The following tables summarize marketable securities held at August 31, 2013 and May 31, 2013 by asset type:
		Available-For-Sale Securities
	(In thousands)	Amortized		Gross			Gross			Fair Value
		Cost		Unrealized			Unrealized			(Net
				Gains			Losses			Carrying
										Amount)
	August 31, 2013
	Equity securities:
	Stocks — foreign	$	1,090	$	367		$	(47	)	$	1,410
	Stocks — domestic		30,931		4,749			(488	)		35,192
	Mutual funds — foreign		26,348		2,018			(148	)		28,218
	Mutual funds — domestic		27,835		233			(1,340	)		26,728
	Total equity securities		86,204		7,367			(2,023	)		91,548
	Fixed maturity:
	U.S. treasury and other government		20,386		166			(341	)		20,211
	Corporate bonds		1,714		192			(1	)		1,905
	Foreign bonds		37		3			—			40
	Mortgage-backed securities		88		58			—			146
	Total fixed maturity securities		22,225		419			(342	)		22,302
	Total	$	108,429	$	7,786		$	(2,365	)	$	113,850
		Available-For-Sale Securities
	(In thousands)	Amortized		Gross			Gross			Fair Value
		Cost		Unrealized			Unrealized			(Net
				Gains			Losses			Carrying
										Amount)
	May 31, 2013
	Equity securities:
	Stocks — foreign	$	1,090	$	244		$	—		$	1,334
	Stocks — domestic		24,492		5,265			(392	)		29,365
	Mutual funds — foreign		18,328		1,901			(7	)		20,222
	Mutual funds — domestic		39,184		679			(492	)		39,371
	Total equity securities		83,094		8,089			(891	)		90,292
	Fixed maturity:
	U.S. treasury and other government		20,528		247			(139	)		20,636
	Corporate bonds		1,724		244			—			1,968
	Foreign bonds		37		4			—			41
	Mortgage-backed securities		100		60			(4	)		156
	Total fixed maturity securities		22,389		555			(143	)		22,801
	Total	$	105,483	$	8,644		$	(1,034	)	$	113,093
Summary of Securities in Unrealized Loss Position and Included in Accumulated Other Comprehensive Income, Aggregated by Length of Time Investments	Summarized below are the securities we held at August 31, 2013 and May 31, 2013 that were in an unrealized loss position and that were included in accumulated other comprehensive income, aggregated by the length of time the investments had been in that position:
		August 31, 2013					May 31, 2013
	(In thousands)	Fair Value		Gross			Fair Value			Gross
				Unrealized						Unrealized
				Losses						Losses
	Total investments with unrealized losses	$	48,861	$	(2,365	)	$	36,582		$	(1,034	)
	Unrealized losses with a loss position for less than 12 months		46,046		(2,277	)		36,327			(956	)
	Unrealized losses with a loss position for more than 12 months		2,815		(88	)		255			(78	)
Net Carrying Values of Debt Securities by Contractual Maturity	The net carrying values of debt securities at August 31, 2013, by contractual maturity, are shown below. Expected maturities may differ from contractual maturities because the issuers of the securities may have the right to prepay obligations without prepayment penalties.
	(In thousands)	Amortized		Fair
		Cost		Value
	Due:
	Less than one year	$	3,081	$	3,093
	One year through five years		13,043		13,100
	Six years through ten years		4,439		4,322
	After ten years		1,662		1,787
		$	22,225	$	22,302

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	3 Months Ended
	Aug. 31, 2013
Assets and Liabilities Measured at Fair Value on Recurring Basis and Categorized using Fair Value Hierarchy	The following tables present our assets and liabilities that are measured at fair value on a recurring basis and are categorized using the fair value hierarchy.
	(In thousands)	Quoted Prices in		Significant			Significant			Fair Value at
		Active Markets		Other			Unobservable			August 31, 2013
		for Identical		Observable			Inputs (Level 3)
		Assets (Level 1)		Inputs (Level 2)
	U.S. Treasury and other government	$	—	$	20,211		$	—		$	20,211
	Foreign bonds				40						40
	Mortgage-backed securities				146						146
	Corporate bonds				1,905						1,905
	Stocks — foreign		1,410								1,410
	Stocks — domestic		35,192								35,192
	Mutual funds — foreign				28,218						28,218
	Mutual funds — domestic				26,728						26,728
	Foreign currency forward contract				1,687						1,687
	Cross-currency swap				(12,708	)					(12,708	)
	Contingent consideration				—			(68,050	)		(68,050	)
	Total	$	36,602	$	66,227		$	(68,050	)	$	34,779
	(In thousands)	Quoted Prices in		Significant			Significant			Fair Value at
		Active Markets		Other			Unobservable			May 31, 2013
		for Identical		Observable			Inputs (Level 3)
		Assets (Level 1)		Inputs (Level 2)
	U.S. Treasury and other government	$	—	$	20,636		$	—		$	20,636
	Foreign bonds				41						41
	Mortgage-backed securities				156						156
	Corporate bonds				1,968						1,968
	Stocks — foreign		1,334								1,334
	Stocks — domestic		29,365								29,365
	Mutual funds — foreign				20,222						20,222
	Mutual funds — domestic				39,371						39,371
	Foreign currency forward contract				(4,751	)					(4,751	)
	Cross-currency swap				(10,048	)					(10,048	)
	Contingent consideration							(64,500	)		(64,500	)
	Total	$	30,699	$	67,595		$	(64,500	)	$	33,794
Fair Value and Carrying Value of Financial Instruments and Long-Term Debt	Based on the analysis performed, the fair value and the carrying value of our financial instruments and long-term debt as of August 31, 2013 and May 31, 2013 are as follows:
		At August 31, 2013
	(In thousands)	Carrying		Fair Value
		Value
	Cash and cash equivalents	$	204,903	$	204,903
	Marketable equity securities		91,548		91,548
	Marketable debt securities		22,302		22,302
	Long-term debt, including current portion		1,424,144		1,504,714
		At May 31, 2013
	(In thousands)	Carrying		Fair Value
		Value
	Cash and cash equivalents	$	343,554	$	343,554
	Marketable equity securities		90,292		90,292
	Marketable debt securities		22,801		22,801
	Long-term debt, including current portion		1,373,697		1,501,850

Contingencies_and_Other_Accrue1

Contingencies and Other Accrued Losses (Tables)	3 Months Ended
	Aug. 31, 2013
Changes in Accrued Warranty Balances	The following table includes the changes in our accrued warranty balances:
			Quarter Ended
			August 31,
	(In thousands)		2013			2012
	Beginning Balance		$	9,330		$	14,751
	Deductions (1)			(4,796	)		(3,905	)
	Provision charged to SG&A expense			5,308			3,681
	Ending Balance		$	9,842		$	14,527
	-1	Primarily claims paid during the year.

Equity_Tables

Equity (Tables)	3 Months Ended
	Aug. 31, 2013
Components of Total Equity and Comprehensive Income	The following tables illustrate the components of total equity and comprehensive income for the three months ended August 31, 2013 and 2012:
	(In thousands)	Total RPM			Noncontrolling			Total Equity
		International			Interest
		Inc. Equity
	Total equity at May 31, 2013	$	1,200,858		$	154,075		$	1,354,933
	Net income		103,098			3,791			106,889
	Other Comprehensive Income:
	Foreign currency translation adjustments		(17,071	)		3,657			(13,414	)
	Pension and other postretirement benefit liability adjustments, net of tax		2,761			163			2,924
	Unrealized (loss) on securities, net of tax		(1,432	)		(7	)		(1,439	)
	Unrealized gain on derivatives, net of tax		86			23			109
	Total Other Comprehensive Income, net of tax		(15,656	)		3,836			(11,820	)
	Comprehensive Income		87,442			7,627			95,069
	Dividends paid		(29,836	)					(29,836	)
	Other noncontrolling interest activity		(341	)		341			—
	Stock option exercises, net		2,401						2,401
	Stock based compensation expense		709						709
	Restricted awards, net		451						451
	Total Equity at August 31, 2013	$	1,261,684		$	162,043		$	1,423,727
	(In thousands)	Total RPM			Noncontrolling			Total Equity
		International			Interest
		Inc. Equity
	Total equity at May 31, 2012	$	1,183,656		$	130,327		$	1,313,983
	Net income		33,913			3,954			37,867
	Other Comprehensive Income:
	Foreign currency translation adjustments		28,664			10,566			39,230
	Pension and other postretirement benefit liability adjustments, net of tax		1,534			(328	)		1,206
	Unrealized gain (loss) on securities, net of tax		825			(1,177	)		(352	)
	Unrealized gain on derivatives, net of tax		169			18			187
	Total Other Comprehensive Income, net of tax		31,192			9,079			40,271
	Comprehensive Income		65,105			13,033			78,138
	Dividends paid		(28,281	)					(28,281	)
	Other noncontrolling interest activity		1,284			—			1,284
	Stock option exercises, net		603						603
	Stock based compensation expense		588						588
	Restricted awards, net		3,285						3,285
	Total Equity at August 31, 2012	$	1,226,240		$	143,360		$	1,369,600

Segment_Information_Tables

Segment Information (Tables)	3 Months Ended
	Aug. 31, 2013
Results of Reportable Segments	The following tables reflect the results of our reportable segments consistent with our management philosophy, and represent the information we utilize, in conjunction with various strategic, operational and other financial performance criteria, in evaluating the performance of our portfolio of businesses.
		Three Months Ended
		August 31,			August 31,
		2013			2012
		(In thousands)
	Net Sales
	Industrial Segment	$	731,226		$	703,335
	Consumer Segment		433,448			343,379
	Consolidated	$	1,164,674		$	1,046,714
	Income (Loss) Before Income Taxes
	Industrial Segment	$	97,581		$	74,304
	Consumer Segment		82,717			58,788
	Corporate/Other		(33,082	)		(61,030	)
	Consolidated	$	147,216		$	72,062
		August 31,			May 31,
		2013			2013
	Identifiable Assets
	Industrial Segment	$	2,335,594		$	2,461,163
	Consumer Segment		1,644,161			1,584,336
	Corporate/Other		83,371			70,027
	Consolidated	$	4,063,126		$	4,115,526

Investment_in_Kemrock_Industri1

Investment in Kemrock Industries and Exports Ltd - Additional Information (Detail)

3 Months Ended

3 Months Ended

12 Months Ended

12 Months Ended

Aug. 31, 2012

31-May-13

Nov. 30, 2012

Aug. 08, 2012

31-May-12

Aug. 31, 2012

31-May-13

31-May-12

31-May-11

31-May-12

31-May-12

31-May-13

31-May-13

USD ($)

INR

INR

INR

Kemrock Industries and Exports Limited

Kemrock Industries and Exports Limited

Kemrock Industries and Exports Limited

Kemrock Industries and Exports Limited

Kemrock global depository receipts

Conversion option, Kemrock 5.5% bonds

Conversion option, Kemrock 5.5% bonds

Embedded Conversion Feature

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Kemrock Industries and Exports Limited

Kemrock Industries and Exports Limited

USD ($)

USD ($)

Basis of Presentation [Line Items]

Acquisition of equity method investment, shares

3,200,000

693,072

Equity method investment, carrying value

$24,200,000

$42,200,000

Equity method investment, ownership percentage

18.00%

Advances to affiliate

10,000,000

15,000,000

Agreement expiration period

15-Sep-12

Purchase of global depository receipt, value

7,200,000

Investment in affiliate

22,700,000

Investment in affiliate, interest rate

5.50%

Kemrock common stock market value per share

43.85

56.7

531

Kemrock common stock price declining percentage

40.00%

Impairment loss on equity method investment

32,100,000

Loans deemed uncollectible, recorded as loss

5,000,000

Loss on Kemrock conversion option

-8,183,000

Impairment on investment in Kemrock

$40,273,000

$42,200,000

$13,700,000

$9,000,000

Deconsolidation_of_Specialty_P1

Deconsolidation of Specialty Products Holding Corp. ("SPHC") - Additional Information (Detail) (USD $)	3 Months Ended
	31-May-10	31-May-12
Reorganization [Line Items]
Number of appeal bonds satisfied		1
Carrying value of retained interest in SPHC	$0
Net loss from deconsolidation of business	($7,900,000)

Investment_Income_Expense_Net_1

Investment (Income) Expense, Net (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Aug. 31, 2013	Aug. 31, 2012
Component Of Other Expense Income Nonoperating [Line Items]
Interest (income)	($1,503)	($2,295)
(Gain) loss on sale of marketable securities	-2,197	-4,584
Other-than-temporary impairment on securities	51	113
Dividend (income)	-245	-208
Investment (income) expense, net	($3,894)	($6,974)

Other_Expense_Income_Net_Detai

Other Expense (Income), Net (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Aug. 31, 2013	Aug. 31, 2012
Component Of Other Expense Income Nonoperating [Line Items]
Royalty expense (income), net	$318	($294)
Loss on Kemrock conversion option		8,183
(Income) loss related to unconsolidated equity affiliates	-752	31,533
Other expense (income), net	($434)	$39,422

RetirementRelated_Benefit_Plan

Retirement-Related Benefit Plans' Impact on Income Before Income Taxes (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Aug. 31, 2013	Aug. 31, 2012
Pension Benefits, U.S. Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$6,764	$6,488
Interest cost	4,510	4,060
Expected return on plan assets	-5,190	-4,358
Amortization of:
Prior service cost (credit)	83	87
Net actuarial (gains) losses recognized	3,306	4,222
Net Periodic Benefit Cost	9,473	10,499
Pension Benefits, Non-U.S. Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	1,109	1,050
Interest cost	1,800	1,769
Expected return on plan assets	-2,095	-1,846
Amortization of:
Prior service cost (credit)	1	2
Net actuarial (gains) losses recognized	623	692
Net Periodic Benefit Cost	1,438	1,667
Postretirement Benefits, U.S. Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Interest cost	81	88
Amortization of:
Prior service cost (credit)	-22	-22
Net actuarial (gains) losses recognized	-29	4
Net Periodic Benefit Cost	30	70
Postretirement Benefits, Non-U.S. Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	327	288
Interest cost	317	289
Amortization of:
Net actuarial (gains) losses recognized	133	114
Net Periodic Benefit Cost	$777	$691

Pension_Plans_Additional_Infor

Pension Plans - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	31-May-13
Pension Benefits, U.S. Plans
Schedule of Pension and Other Postretirement Benefits Expected Benefit Payments [Line Items]
Contribution to retirement plans in current fiscal year	$27.40
Pension Benefits, Non-U.S. Plans
Schedule of Pension and Other Postretirement Benefits Expected Benefit Payments [Line Items]
Contribution to retirement plans in current fiscal year	$7.40

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Aug. 31, 2013	Aug. 31, 2012
Income Tax [Line Items]
Effective income tax rate	27.40%	47.50%
Federal Statutory Rate	35.00%	35.00%
Unrecognized tax benefits	$15
Unrecognized tax benefits that would impact effective tax rate, if recognized	14.1
Accrued interest and penalties related to unrecognized tax benefits	$5.80

Reconciliation_of_Numerator_an

Reconciliation of Numerator and Denominator of Basic and Diluted Earnings Per Share, Calculated using Two-Class Method (Detail) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Aug. 31, 2013		Aug. 31, 2012
Numerator for earnings per share:
Net income attributable to RPM International Inc. stockholders	$103,098		$33,913
Less: Allocation of earnings and dividends to participating securities	-2,285		-642
Net income available to common shareholders - basic	100,813		33,271
Add: Undistributed earnings reallocated to unvested shareholders	12		1
Net income available to common shareholders - diluted	$100,825		$33,272
Denominator for basic and diluted earnings per share:
Basic weighted average common shares	129,344		128,805
Average diluted options	950		765
Total shares for diluted earnings per share	130,294		129,570
Earnings Per Share of Common Stock Attributable to RPM International Inc. Stockholders:
Basic	$0.78		$0.26
Diluted	$0.77	[1]	$0.26	[1]
[1]	For the quarters ended August 31, 2013 and 2012, approximately 3,097,000 and 2,954,000 shares of stock, respectively, granted under stock-based compensation plans were excluded from the calculation of diluted earnings per share, as the effect would have been anti-dilutive.

Reconciliation_of_Numerator_an1

Reconciliation of Numerator and Denominator of Basic and Diluted Earnings Per Share, Calculated using Two-Class Method (Parenthetical) (Detail)	3 Months Ended
	Aug. 31, 2013	Aug. 31, 2012
Earnings Per Share Disclosure [Line Items]
Stock-based compensation plans, excluded from the calculation of diluted earnings per share, anti-dilutive shares of stock	3,097,000	2,954,000

Major_Classes_of_Inventories_D

Major Classes of Inventories (Detail) (USD $)	Aug. 31, 2013	31-May-13
In Thousands, unless otherwise specified
Inventory [Line Items]
Raw material and supplies	$190,910	$185,590
Finished goods	381,238	363,090
Total Inventory	$572,148	$548,680

Restructuring_Additional_Infor

Restructuring - Additional Information (Detail) (USD $)	3 Months Ended		1 Months Ended
	Aug. 31, 2013	Aug. 31, 2013	31-May-13	31-May-13	31-May-13	31-May-13	31-May-13
		Employee Severance	Consumer Segment	Consumer Segment	Consumer Segment	Industrial Segment	Industrial Segment
			Two Thousand Thirteen Plan	Two Thousand Thirteen Plan	Two Thousand Thirteen Plan	Two Thousand Thirteen Plan	Two Thousand Thirteen Plan
			Facility	Employee Severance	Facility Closing		Employee Severance
			Position				Position
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$128,000	$128,000	$15,600,000	$8,200,000	$7,400,000	$4,500,000
Number of position eliminated			133
Number of shutdown manufacturing facilities			2
Inventory markdowns			$3,900,000
Expected number of positions to be eliminated							34

Changes_in_Accrued_Restructuri

Changes in Accrued Restructuring Balances (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Aug. 31, 2013
Restructuring Cost and Reserve [Line Items]
Balance at May 31, 2013	$17,782
Charge to expense	128
Cash payments	-1,416
Noncash and foreign exchange impacts	298
Balance at August 31, 2013	16,792
Long-Lived Asset Charges
Restructuring Cost and Reserve [Line Items]
Balance at May 31, 2013	4,729
Noncash and foreign exchange impacts	123
Balance at August 31, 2013	4,852
Employee Severance
Restructuring Cost and Reserve [Line Items]
Balance at May 31, 2013	12,656
Charge to expense	128
Cash payments	-1,416
Noncash and foreign exchange impacts	165
Balance at August 31, 2013	11,533
Site Preparation and Equipment Relocation
Restructuring Cost and Reserve [Line Items]
Balance at May 31, 2013	397
Noncash and foreign exchange impacts	10
Balance at August 31, 2013	$407

Summary_of_Marketable_Securiti

Summary of Marketable Securities by Asset Type (Detail) (USD $)	Aug. 31, 2013	31-May-13
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	$108,429	$105,483
Available-for-Sale Securities, Gross Unrealized Gains	7,786	8,644
Available-for-Sale Securities, Gross Unrealized Losses	-2,365	-1,034
Available-for-Sale Securities, Fair Value (Net Carrying Amount)	113,850	113,093
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	86,204	83,094
Available-for-Sale Securities, Gross Unrealized Gains	7,367	8,089
Available-for-Sale Securities, Gross Unrealized Losses	-2,023	-891
Available-for-Sale Securities, Fair Value (Net Carrying Amount)	91,548	90,292
Equity securities | Stocks | Foreign
Schedule of Available-for-sale Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	1,090	1,090
Available-for-Sale Securities, Gross Unrealized Gains	367	244
Available-for-Sale Securities, Gross Unrealized Losses	-47
Available-for-Sale Securities, Fair Value (Net Carrying Amount)	1,410	1,334
Equity securities | Stocks | Domestic
Schedule of Available-for-sale Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	30,931	24,492
Available-for-Sale Securities, Gross Unrealized Gains	4,749	5,265
Available-for-Sale Securities, Gross Unrealized Losses	-488	-392
Available-for-Sale Securities, Fair Value (Net Carrying Amount)	35,192	29,365
Equity securities | Mutual funds | Foreign
Schedule of Available-for-sale Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	26,348	18,328
Available-for-Sale Securities, Gross Unrealized Gains	2,018	1,901
Available-for-Sale Securities, Gross Unrealized Losses	-148	-7
Available-for-Sale Securities, Fair Value (Net Carrying Amount)	28,218	20,222
Equity securities | Mutual funds | Domestic
Schedule of Available-for-sale Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	27,835	39,184
Available-for-Sale Securities, Gross Unrealized Gains	233	679
Available-for-Sale Securities, Gross Unrealized Losses	-1,340	-492
Available-for-Sale Securities, Fair Value (Net Carrying Amount)	26,728	39,371
Fixed securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	22,225	22,389
Available-for-Sale Securities, Gross Unrealized Gains	419	555
Available-for-Sale Securities, Gross Unrealized Losses	-342	-143
Available-for-Sale Securities, Fair Value (Net Carrying Amount)	22,302	22,801
Fixed securities | U.S. Treasury and other government
Schedule of Available-for-sale Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	20,386	20,528
Available-for-Sale Securities, Gross Unrealized Gains	166	247
Available-for-Sale Securities, Gross Unrealized Losses	-341	-139
Available-for-Sale Securities, Fair Value (Net Carrying Amount)	20,211	20,636
Fixed securities | Corporate bonds
Schedule of Available-for-sale Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	1,714	1,724
Available-for-Sale Securities, Gross Unrealized Gains	192	244
Available-for-Sale Securities, Gross Unrealized Losses	-1
Available-for-Sale Securities, Fair Value (Net Carrying Amount)	1,905	1,968
Fixed securities | Foreign bonds
Schedule of Available-for-sale Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	37	37
Available-for-Sale Securities, Gross Unrealized Gains	3	4
Available-for-Sale Securities, Fair Value (Net Carrying Amount)	40	41
Fixed securities | Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-Sale Securities, Amortized Cost	88	100
Available-for-Sale Securities, Gross Unrealized Gains	58	60
Available-for-Sale Securities, Gross Unrealized Losses		-4
Available-for-Sale Securities, Fair Value (Net Carrying Amount)	$146	$156

Marketable_Securities_Addition

Marketable Securities - Additional Information (Detail) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Aug. 31, 2013	Aug. 31, 2012	31-May-13
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, current	$52		$49.10
Available-for-sale securities, long-term	61.9		64
Gross gains realized on sales of investments	2.2	5
Gross losses realized on sales of investments		0.4
Losses recognized for securities deemed to have other-than-temporary impairments	$0.10	$0.10
Maximum
Schedule of Available-for-sale Securities [Line Items]
Investments with unrealized loss, percentage of fair values less than original cost	15.00%

Summary_of_Securities_in_Unrea

Summary of Securities in Unrealized Loss Position and Included in Accumulated Other Comprehensive Income, Aggregated by Length of Time Investments (Detail) (USD $)	Aug. 31, 2013	31-May-13
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]
Total investments with unrealized losses, fair value	$48,861	$36,582
Unrealized losses with a loss position for less than 12 months, fair value	46,046	36,327
Unrealized losses with a loss position for more than 12 months, fair value	2,815	255
Total investments with unrealized losses, gross unrealized losses	-2,365	-1,034
Unrealized losses with a loss position for less than 12 months, gross unrealized losses	-2,277	-956
Unrealized losses with a loss position for more than 12 months, gross unrealized losses	($88)	($78)

Net_Carrying_Values_of_Debt_Se

Net Carrying Values of Debt Securities by Contractual Maturity (Detail) (USD $)	Aug. 31, 2013	31-May-13
In Thousands, unless otherwise specified
Available-for-Sale Securities, amortized cost
Less than one year, amortized cost	$3,081
One year through five years, amortized cost	13,043
Six years through ten years, amortized cost	4,439
After ten years, amortized cost	1,662
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	22,225
Available-for-Sale Securities, fair value
Less than one year, fair value	3,093
One year through five years, fair value	13,100
Six years through ten years, fair value	4,322
After ten years, fair value	1,787
Marketable debt securities, carrying value	$22,302	$22,801

Assets_and_Liabilities_Measure

Assets and Liabilities Measured at Fair Value on Recurring Basis and Categorized using Fair Value Hierarchy (Detail) (Fair Value, Measurements, Recurring, USD $)	Aug. 31, 2013	31-May-13
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	($68,050)	($64,500)
Assets (liabilities) at fair value	34,779	33,794
Foreign currency forward contract
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign currency forward contract	1,687
Foreign currency contracts, fair value of liability		-4,751
Cross-currency swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign currency contracts, fair value of liability	-12,708	-10,048
U.S. Treasury and other government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	20,211	20,636
Foreign bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	40	41
Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	146	156
Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	1,905	1,968
Stocks | Foreign
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	1,410	1,334
Stocks | Domestic
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	35,192	29,365
Mutual funds | Foreign
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	28,218	20,222
Mutual funds | Domestic
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	26,728	39,371
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets (liabilities) at fair value	36,602	30,699
Quoted Prices in Active Markets for Identical Assets (Level 1) | Stocks | Foreign
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	1,410	1,334
Quoted Prices in Active Markets for Identical Assets (Level 1) | Stocks | Domestic
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	35,192	29,365
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets (liabilities) at fair value	66,227	67,595
Significant Other Observable Inputs (Level 2) | Foreign currency forward contract
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign currency forward contract	1,687
Foreign currency contracts, fair value of liability		-4,751
Significant Other Observable Inputs (Level 2) | Cross-currency swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign currency contracts, fair value of liability	-12,708	-10,048
Significant Other Observable Inputs (Level 2) | U.S. Treasury and other government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	20,211	20,636
Significant Other Observable Inputs (Level 2) | Foreign bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	40	41
Significant Other Observable Inputs (Level 2) | Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	146	156
Significant Other Observable Inputs (Level 2) | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	1,905	1,968
Significant Other Observable Inputs (Level 2) | Mutual funds | Foreign
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	28,218	20,222
Significant Other Observable Inputs (Level 2) | Mutual funds | Domestic
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on recurring basis	26,728	39,371
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	-68,050	-64,500
Assets (liabilities) at fair value	($68,050)	($64,500)

Fair_Value_Measurements_Additi

Fair Value Measurements - Additional Information (Detail)	Aug. 31, 2013	Aug. 31, 2013	Aug. 31, 2013	Aug. 31, 2013	31-May-13	Aug. 31, 2013	31-May-13
	USD ($)	EUR (€)	Unsecured Senior Notes	Fair Value, Measurements, Recurring	Fair Value, Measurements, Recurring	Fair Value, Measurements, Recurring	Fair Value, Measurements, Recurring
				Foreign currency forward contract	Foreign currency forward contract	Cross-currency swap	Cross-currency swap
				USD ($)	USD ($)	USD ($)	USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign currency contracts, fair value of liability					$4,751,000	$12,708,000	$10,048,000
Debt, interest rate			6.70%
Debt, due date			1-Nov-15
Effective euro fixed-rate borrowing	5.31%	5.31%
Notional principal amount of cross-currency swap	150,000,000	125,000,000
Foreign currency forward contract				$1,687,000

Fair_Value_and_Carrying_Value_

Fair Value and Carrying Value of Financial Instruments and Long-Term Debt (Detail) (USD $)	Aug. 31, 2013	31-May-13	Aug. 31, 2012	31-May-12
In Thousands, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents, carrying value	$204,903	$343,554	$257,382	$315,968
Marketable equity securities, carrying value	91,548	90,292
Marketable debt securities, carrying value	22,302	22,801
Long-term debt, including current portion, carrying value	1,424,144	1,373,697
Cash and cash equivalents, fair value	204,903	343,554
Marketable securities, fair value	113,850	113,093
Long-term debt, including current portion, fair value	1,504,714	1,501,850
Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable securities, fair value	91,548	90,292
Fixed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable securities, fair value	$22,302	$22,801

Reorganization_Proceedings_of_1

Reorganization Proceedings of Certain Subsidiaries - Additional Information (Detail) (USD $)	12 Months Ended
	31-May-10	31-May-08	31-May-08	31-May-13	30-May-10	31-May-06
			Subsidiaries	Subsidiaries	Subsidiaries	Subsidiaries
Reorganization [Line Items]
Current and future asbestos claims				$1,170,000,000
Asbestos-related products liability claims paid	92,600,000
Asbestos-related products liability, defense-related payments	42,600,000
Accrued liability for asbestos			559,700,000		397,700,000	421,300,000
Asbestos liability, term		10 years
Increase in Asbestos liability			$288,100,000

Changes_in_Accrued_Warranty_Ba

Changes in Accrued Warranty Balances (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Aug. 31, 2013		Aug. 31, 2012
Product Liability Contingency [Line Items]
Beginning Balance	$9,330		$14,751
Deductions	-4,796	[1]	-3,905	[1]
Provision charged to SG&A expense	5,308		3,681
Ending Balance	$9,842		$14,527
[1]	Primarily claims paid during the year.

Contingencies_and_Other_Accrue2

Contingencies and Other Accrued Losses - Additional Information (Detail) (USD $)	3 Months Ended
	Aug. 31, 2013	31-May-13
Schedule Of Commitments And Contingencies [Line Items]
Accrued contingencies		$65,100,000
(Decrease) in contingent payment	-61,894,000
Expected payment to resolve issues arising out of investigation and other related costs	$3,200,000

Stock_Repurchase_Program_Addit

Stock Repurchase Program - Additional Information (Detail)	3 Months Ended
In Millions, unless otherwise specified	Aug. 31, 2013
Stock Repurchase Programs [Line Items]
Authorization of stock repurchase program	8-Jan-08
Shares repurchased	0
Minimum
Stock Repurchase Programs [Line Items]
Shares authorized to be repurchased, per year	1
Maximum
Stock Repurchase Programs [Line Items]
Shares authorized to be repurchased, per year	2

Components_of_Total_Equity_and

Components of Total Equity and Comprehensive Income (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Aug. 31, 2013	Aug. 31, 2012
Stockholders Equity Note [Line Items]
Total equity, beginning of period	$1,354,933	$1,313,983
Net income	106,889	37,867
Other Comprehensive Income:
Foreign currency translation adjustments	-13,414	39,230
Pension and other postretirement benefit liability adjustments, net of tax	2,924	1,206
Unrealized (loss) on securities, net of tax	-1,439	-352
Unrealized gain (loss) on derivatives, net of tax	109	187
Total Other Comprehensive (Loss) Income	-11,820	40,271
Total Comprehensive Income	95,069	78,138
Dividends paid	-29,836	-28,281
Other noncontrolling interest activity		1,284
Stock option exercises, net	2,401	603
Stock based compensation expense	709	588
Restricted awards, net	451	3,285
Total Equity, end of period	1,423,727	1,369,600
Total RPM International Inc. Equity
Stockholders Equity Note [Line Items]
Total equity, beginning of period	1,200,858	1,183,656
Net income	103,098	33,913
Other Comprehensive Income:
Foreign currency translation adjustments	-17,071	28,664
Pension and other postretirement benefit liability adjustments, net of tax	2,761	1,534
Unrealized (loss) on securities, net of tax	-1,432	825
Unrealized gain (loss) on derivatives, net of tax	86	169
Total Other Comprehensive (Loss) Income	-15,656	31,192
Total Comprehensive Income	87,442	65,105
Dividends paid	-29,836	-28,281
Other noncontrolling interest activity	-341	1,284
Stock option exercises, net	2,401	603
Stock based compensation expense	709	588
Restricted awards, net	451	3,285
Total Equity, end of period	1,261,684	1,226,240
Noncontrolling Interest
Stockholders Equity Note [Line Items]
Total equity, beginning of period	154,075	130,327
Net income	3,791	3,954
Other Comprehensive Income:
Foreign currency translation adjustments	3,657	10,566
Pension and other postretirement benefit liability adjustments, net of tax	163	-328
Unrealized (loss) on securities, net of tax	-7	-1,177
Unrealized gain (loss) on derivatives, net of tax	23	18
Total Other Comprehensive (Loss) Income	3,836	9,079
Total Comprehensive Income	7,627	13,033
Other noncontrolling interest activity	341
Total Equity, end of period	$162,043	$143,360

Segment_Information_Additional

Segment Information - Additional Information (Detail)	3 Months Ended
	Aug. 31, 2013
	Segment
Segment Reporting Information [Line Items]
Number of reportable segments	2
Number of operating segments	7

Results_of_Reportable_Segments

Results of Reportable Segments (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Aug. 31, 2013	Aug. 31, 2012	31-May-13
Segment Reporting Information [Line Items]
Net Sales	$1,164,674	$1,046,714
Income (Loss) Before Income Taxes	147,216	72,062
Total Assets	4,063,126	4,115,526	4,115,526
Industrial Segment
Segment Reporting Information [Line Items]
Net Sales	731,226	703,335
Income (Loss) Before Income Taxes	97,581	74,304
Total Assets	2,335,594	2,461,163
Consumer Segment
Segment Reporting Information [Line Items]
Net Sales	433,448	343,379
Income (Loss) Before Income Taxes	82,717	58,788
Total Assets	1,644,161	1,584,336
Corporate/Other
Segment Reporting Information [Line Items]
Income (Loss) Before Income Taxes	-33,082	-61,030
Total Assets	$83,371	$70,027