Document and Entity Information	9 Months Ended
	Aug. 31, 2019 $ / shares shares
Document and Entity Information [Abstract]
Title of 12(b) Security	Common Stock
Entity Incorporation, State or Country Code	OH
Document Type	10-Q
Document Period End Date	Aug. 31, 2019
Entity File Number	1-15147
Entity Registrant Name	OMNOVA SOLUTIONS INC
Entity Address, Address Line One	25435 Harvard Road
Entity Address, City or Town	Beachwood
Entity Address, State or Province	OH
Entity Address, Postal Zip Code	44122-6201
City Area Code	216
Local Phone Number	682-7000
Document Fiscal Year Focus	2019
Entity Common Stock, Shares Outstanding | shares	44,853,732
Entity Listing, Par Value Per Share | $ / shares	$ 0.10
Amendment Flag	false
Current Fiscal Year End Date	--11-30
Document Fiscal Period Focus	Q3
Entity Central Index Key	0001090061
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Tax Identification Number	34-1897652
Trading Symbol	OMN
Security Exchange Name	NYSE
Document Quarterly Report	true
Document Transition Report	false