XML 67 R55.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Investment Expense (Income), Net - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Nov. 30, 2018 | Nov. 30, 2017 | Nov. 30, 2018 | Nov. 30, 2017
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |  |
Gross realized losses on sales of marketable securities | $ 1.0 |  | $ 1.2 | $ 1.2
Unrealized losses on trading securities | 1.0 |  | 1.1 |
Gross gains realized on sales of marketable securities |  | $ 2.0 | 0.2 | $ 6.1
Unrealized gains on trading securities |  |  | 0.5 |
ASU 2016-01 |  |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |  |
Unrealized losses on marketable equity securities | $ 6.5 |  | $ 6.5 |

X
- Definition Gross realized gains on sales of marketable securities. + References No definition available. + Details
Name: | rpm_GrossRealizedGainsOnSalesOfMarketableSecurities
Namespace Prefix: | rpm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Gross realized losses on sales of marketable securities. + References No definition available. + Details
Name: | rpm_GrossRealizedLossesOnSalesOfMarketableSecurities
Namespace Prefix: | rpm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of unrealized gain on investment in debt security measured at fair value with change in fair value recognized in net income (trading). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563 + Details
Name: | us-gaap_DebtSecuritiesTradingUnrealizedGain
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of unrealized loss on investment in debt security measured at fair value with change in fair value recognized in net income (trading). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563 + Details
Name: | us-gaap_DebtSecuritiesTradingUnrealizedLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of unrealized loss on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117546-209714 + Details
Name: | us-gaap_EquitySecuritiesFvNiUnrealizedLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201601Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |