Leases - Components of lease expense (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Leases
Impairment of leasehold and right of use assets	$ 86.2
Operating lease cost
Operating lease cost		$ 149.1	$ 164.0	$ 172.5
Finance lease cost:
Amortization of right-of-use assets		28.4	23.1	18.0
Interest on lease liabilities		2.9	2.6	2.2
Variable lease cost		34.6	34.1	34.0
Total lease cost		$ 215.0	$ 223.8	$ 226.7

No definition available.

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- Definition

Amount of interest expense on finance lease liability.

+ References

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- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

+ References

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- Definition

The adjustment to reduce the value of existing agreements that specify the lessee's rights to use the leased property. This expense is charged when the estimates of future profits generated by the leased property are reduced.

+ References

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- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

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- References

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

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- Definition

Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

+ References

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