Retirement Benefits (Components Recognized in Accumulated Other Comprehensive Income on Pretax Basis) (Details) - Defined Benefit Pension Plan - USD ($) $ in Millions	Sep. 30, 2022	Sep. 30, 2021
U.S.
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss	$ 525.5	$ 444.7
Prior service cost	6.5	6.3
Net transition liability	0.0	0.0
Total	532.0	451.0
International
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss	511.6	535.8
Prior service cost	3.7	3.6
Net transition liability	0.4	0.4
Total	$ 515.7	$ 539.8

Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount, before tax, of accumulated other comprehensive income (loss) for transition asset (obligation) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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-Publisher FASB
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