Inventories (Details) - USD ($) $ in Thousands	Apr. 30, 2019	Apr. 30, 2018
Inventory Disclosure [Abstract]
Raw materials	$ 46,054	$ 41,728
Work-in-process	43,794	44,905
Finished goods	34,873	34,111
Total FIFO inventories	124,721	120,744
Reserve to adjust inventories to LIFO value	(16,193)	(15,943)
Total inventory	108,528	104,801
Carried under FIFO	58,600	56,600
Carried under LIFO	$ 49,900	$ 48,200

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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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.

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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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