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Description of Business and Significant Accounting Policies - Additional Information (Details) $ / shares in Units, $ in Millions	9 Months Ended	12 Months Ended
	Aug. 31, 2019 USD ($) $ / shares	Nov. 30, 2019 USD ($) segment	Nov. 30, 2018 USD ($) $ / shares	Nov. 30, 2017 USD ($) $ / shares	Feb. 28, 2019 USD ($)	Nov. 30, 2016 USD ($)
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Common stock, par value \| $ / shares	$ 0.10		$ 0.10	$ 0.10
Number of Reportable Segments \| segment		2
Other Research and Development Expense		$ 18.2	$ 17.7	$ 18.9
Research and Development Expense		6.2	6.1	7.5
Derivative, Notional Amount		16.6	16.5
Foreign Currency Contract, Asset, Fair Value Disclosure		0.0	0.1
Allowance for doubtful accounts		$ 3.4	$ 3.3	2.9		$ 0.8
Percentage of LIFO Inventory		47.20%	45.90%
Reserve for inventory obsolescence		$ (6.1)	$ (6.9)
Goodwill		69.4	70.9	66.3
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)		7.8	1.5
Capital Leases, Future Minimum Payments, Present Value of Net Minimum Payments		14.9
Cumulative Effect of New Accounting Principle in Period of Adoption		0.5	6.9	(2.9)	$ 0.5
Performance Materials [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Goodwill		$ 0.0	0.0	0.0
Goodwill, Impairment Loss				$ 19.6
Minimum [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Finite-lived intangible asset useful life		3 years
Maximum [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Finite-lived intangible asset useful life		53 years
Foreign Exchange Contract [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Derivative, Notional Amount		$ 16.6	$ 16.5
Synthomer and OMNOVA Merger [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Business Acquisition, Share Price \| $ / shares	$ 10.15
Loss Contingency, Damages Sought, Value	$ 15.8