Leases - Components of Lease Expense (Detail) - USD ($) $ in Thousands	3 Months Ended
Jul. 31, 2020	Jul. 31, 2019
Finance lease cost
Amortization of ROU assets	$ 338	$ 470
Interest on lease liabilities	31	40
Finance lease cost	369	510
Operating lease cost	13,983	14,227
Short-term lease cost	108	279
Variable lease cost	2,407	2,893
Sublease income	(80)	(54)
Total lease cost	$ 16,787	$ 17,855

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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- Definition

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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- 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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-Publisher FASB
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- Definition

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

+ References

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- Definition

Amount of sublease income excluding finance and operating lease expense.

+ 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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