Fair Value Measurements - Non-Recurring Fair Value Measurements (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Nov. 30, 2024	Feb. 28, 2025	Feb. 29, 2024	Feb. 28, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of goodwill	$ 0.0	$ 0.0	$ 34.8	$ 245.4
Goodwill impairment loss - disc. op		0.0	18.9	133.3
Impairment of goodwill (note 4)		0.0	15.9	112.1
Impairment of long-lived assets total (note 3)		9.6	15.3	234.5
Impairment of long-lived assets (note 4)		9.6	15.3	3.5
Impairment Of Right of Use Assets		6.9	6.9	3.5
Patent Abandonment, Cost			15.3
Patent Abandonment, Accumulated Amortization			7.5
Patent Abandonment classified as impairment of LLA, Net Book Value			7.8
Impairment Of Right of Use Asset and related Property, Plant and Equipment			7.5
Other Intangible Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long Lived Asset impairment discontinued operations				$ 231.0
Property, Plant and Equipment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of long-lived assets (note 4)		2.7	$ 0.6
Other Intangible Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of long-lived assets (note 4)		$ 0.5