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Retirement Plans (Accumulated and Projected Benefit Obligations) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Sep. 30, 2018
Pension Plans with accumulated benefit obligations in excess of plan assets
Projected benefit obligation	$ 356.6	$ 6.3
Accumulated benefit obligation	356.6	6.3
Fair value of plan assets	351.6	5.0
Pension plans with plan assets in excess of accumulated benefit obligations
Projected benefit obligation	0.0	327.1
Accumulated benefit obligation	0.0	327.1
Fair value of plan assets	$ 0.0	$ 338.5

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Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

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