Leases - Components of Lease Expense (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2020	Oct. 31, 2019
Finance lease cost
Amortization of ROU assets	$ 317	$ 473	$ 655	$ 943
Interest on lease liabilities	30	39	61	79
Finance lease cost	347	512	716	1,022
Operating lease cost	14,027	14,166	28,010	28,393
Short-term lease cost	104	277	212	556
Variable lease cost	2,785	3,183	5,192	6,076
Sublease income	(195)	(53)	(275)	(107)
Total lease cost	$ 17,068	$ 18,085	$ 33,855	$ 35,940

Finance lease costs.

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- Definition

Finance lease costs.

+ References

No definition available.

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- Definition

Amount of interest expense on finance lease liability.

+ References

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

+ References

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- Definition

Amount of lease cost recognized by lessee for lease contract.

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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.

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-Publisher FASB
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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

+ References

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Amount of sublease income excluding finance and operating lease expense.

+ References

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

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