Document and Entity Information	9 Months Ended
	Aug. 28, 2011	Sep. 19, 2011
Entity Information [Line Items]
Entity Registrant Name	AMERON INTERNATIONAL CORPORATION
Entity Central Index Key	0000790730
Current Fiscal Year End Date	--11-30
Document Fiscal Year Focus	2011
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Aug. 28, 2011
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		9,069,126
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes