Inventories (Details) - USD ($) $ in Thousands	Apr. 30, 2021	Apr. 30, 2020
Inventory Disclosure [Abstract]
Raw materials	$ 63,384	$ 51,460
Work-in-process	51,176	42,381
Finished goods	43,526	32,572
Total FIFO inventories	158,086	126,413
Reserve to adjust inventories to LIFO value	(17,804)	(14,577)
Total inventory	140,282	111,836
Carried under FIFO	80,300	66,000
Carried under LIFO	$ 60,000	$ 45,800

The amount of FIFO (first in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

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-Section 50
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- References

No definition available.

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- Definition

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

+ References

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

+ References

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Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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The amount of LIFO (last in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

+ References

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