Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2017
Property and equipment
Total property and equipment	$ 405,932	$ 249,343
Less: accumulated depreciation and amortization	123,583	85,761
Property, Plant and Equipment, Net, Total	282,349	163,582
Depreciation and amortization expense for property and equipment	46,500	24,100	$ 25,600
Land
Property and equipment
Total property and equipment	52,031	50,795
Buildings and leasehold improvements
Property and equipment
Total property and equipment	99,300	87,837
Machinery and equipment
Property and equipment
Total property and equipment	252,504	108,444
Construction in progress
Property and equipment
Total property and equipment	$ 2,097	$ 2,267

Cash flow impact of depreciation and amortization of property and equipment.

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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+ References

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