COMBINED STATEMENTS OF EARNINGS AND COMPREHENSIVE INCOME (Condensed) Parenthetical - USD ($) $ in Millions	9 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Pension/postretirement activity, tax	$ 0.5	$ 0.2
Deferred (loss)/gain on hedging activity, tax	(0.6)	$ (1.9)
Income tax benefit attributable to discontinued operations	$ (0.4)

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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