COMBINED STATEMENTS OF EARNINGS AND COMPREHENSIVE INCOME (Condensed) Parenthetical - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Income Statement [Abstract]
Pension/postretirement activity, tax	$ 0.8	$ 1.2	$ 1.3	$ 1.7
Deferred (loss)/gain on hedging activity, tax	$ 6.7	(1.2)	$ 5.8	(2.2)
Income tax benefit attributable to discontinued operations		$ 13.7		$ 6.2

Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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