Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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Commitments and Contingencies - Capital Leases (Details) $ in Millions	12 Months Ended
	Apr. 30, 2019 USD ($) property	Apr. 30, 2018 USD ($)	Apr. 30, 2017 USD ($)
Capital leases
Carrying value of property and equipment under capital leases	$ 107.3	$ 17.9
Accumulated depreciation on property and equipment under capital leases	27.7	10.3
Rent expense under operating leases	53.5	$ 63.9	$ 56.2
Capital lease assets	73.6
Capital lease obligations	$ 73.6
Minimum
Capital leases
Renewal option period	1 year
Maximum
Capital leases
Renewal option period	5 years
Facility
Capital leases
Number of properties under capital lease \| property	1
Capital lease obligations \| Equipment \| Minimum
Capital leases
Term	5 years
Capital lease obligations \| Equipment \| Maximum
Capital leases
Term	6 years
Capital lease obligations \| Vehicles and trucks \| Minimum
Capital leases
Term	1 year
Capital lease obligations \| Vehicles and trucks \| Maximum
Capital leases
Term	6 years
Capital lease obligations \| Facility
Capital leases
Term	11 years