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Business Segment Information - Additional Information (Details) $ in Millions	3 Months Ended								12 Months Ended
	Nov. 30, 2018 USD ($)	Aug. 31, 2018 USD ($)	May 31, 2018 USD ($)	Feb. 28, 2018 USD ($)	Nov. 30, 2017 USD ($)	Aug. 31, 2017 USD ($)	May 31, 2017 USD ($)	Feb. 28, 2017 USD ($)	Nov. 30, 2018 USD ($) segment	Nov. 30, 2017 USD ($)	Nov. 30, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments \| segment									2
Restructuring and severance	$ 1.7	$ 0.3	$ 0.2	$ 1.3	$ 0.6	$ 0.4	$ 3.6	$ 1.0	$ 3.5	$ 5.7	$ 11.1
Asset impairments	$ 3.9	$ 9.2	$ 0.4	$ 0.0	$ 19.6	$ 0.4	$ 12.9	$ 0.0	13.5	32.9	5.7
Acquisition and integration related expense									4.1	0.3	0.9
Restructuring and Related Cost, Accelerated Depreciation									1.2		3.0
Specialty Solutions [Member]
Segment Reporting Information [Line Items]
Asset impairments									1.1	0.3	0.2
Performance Materials [Member]
Segment Reporting Information [Line Items]
Asset impairments									14.3	33.6	4.2
Acquisition and integration related expense											1.1
Restructuring and Related Cost, Accelerated Depreciation									1.1		3.0
Environmental Remediation Expense									0.2	(2.0)	0.3
Operational improvement costs											0.4
Employee Severance [Member]
Segment Reporting Information [Line Items]
Restructuring and severance									2.7	5.2	8.4
Employee Severance [Member] \| Specialty Solutions [Member]
Segment Reporting Information [Line Items]
Restructuring and severance									0.7	0.6	0.2
Acquisition and integration related expense									1.8
Restructuring and Related Cost, Accelerated Depreciation									0.1
Employee Severance [Member] \| Performance Materials [Member]
Segment Reporting Information [Line Items]
Restructuring and severance									$ 1.1	$ 1.7	$ 3.3