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Business Segment Information - Additional Information (Details) $ in Millions	3 Months Ended								12 Months Ended
	Nov. 30, 2019 USD ($)	Aug. 31, 2019 USD ($)	May 31, 2019 USD ($)	Feb. 28, 2019 USD ($)	Nov. 30, 2018 USD ($)	Aug. 31, 2018 USD ($)	May 31, 2018 USD ($)	Feb. 28, 2018 USD ($)	Nov. 30, 2019 USD ($) segment	Nov. 30, 2018 USD ($)	Nov. 30, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments \| segment									2
Restructuring and severance	$ 0.6	$ 0.8	$ 2.8	$ 1.1	$ 1.7	$ 0.3	$ 0.2	$ 1.3	$ 5.3	$ 3.5	$ 5.7
Asset impairments	$ 6.8	$ 1.0	$ 0.0	$ 0.0	$ 3.9	$ 9.2	$ 0.4	$ 0.0	7.8	13.5	32.9
Acquisition and integration related expense									10.1	4.1	0.3
Restructuring and Related Cost, Accelerated Depreciation									1.1	1.2
Specialty Solutions [Member]
Segment Reporting Information [Line Items]
Asset impairments										1.1	0.3
Performance Materials [Member]
Segment Reporting Information [Line Items]
Asset impairments									10.7	14.3	33.6
Restructuring and Related Cost, Accelerated Depreciation									1.1
Environmental Remediation Expense										0.2	2.0
Employee Severance [Member]
Segment Reporting Information [Line Items]
Restructuring and severance									2.9	2.7	5.2
Employee Severance [Member] \| Specialty Solutions [Member]
Segment Reporting Information [Line Items]
Restructuring and severance									0.4	0.7	0.6
Acquisition and integration related expense									0.3
Employee Severance [Member] \| Performance Materials [Member]
Segment Reporting Information [Line Items]
Restructuring and severance									$ 2.2	$ 1.1	$ 1.7