Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended				12 Months Ended
	Dec. 31, 2017	Nov. 30, 2019	Feb. 28, 2019	Feb. 28, 2018	Feb. 28, 2017	Nov. 30, 2019	Nov. 30, 2018
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	35.00%	21.00%
Deferred Tax Assets
Accrued estimated costs		$ 5.5				$ 5.5	$ 5.7
Inventory		6.3				6.3	6.1
Goodwill and intangible assets		0.0				0.0	0.0
Depreciation		0.0				0.0	0.0
Pension		18.0				18.0	12.6
NOLC’s and other carryforwards		26.1				26.1	37.3
Post-retirement employee benefits		2.5				2.5	2.3
Other		1.9				1.9	0.0
Valuation allowance		(43.5)				(43.5)	(53.2)
Deferred Tax Assets, Net		16.8				16.8	10.8
Deferred Tax Liabilities
Accrued estimated costs		0.0				0.0	0.0
Inventory		0.0				0.0	0.0
Goodwill and intangible assets		8.4				8.4	11.2
Depreciation		18.9				18.9	12.4
Other		0.0				0.0	0.4
Deferred Tax Liabilities		$ 27.3				27.3	$ 24.0
GILTI			$ 27.7	$ 0.0	$ 0.0	$ (3.9)