Inventories (Components Of Inventories) (Details) - USD ($) $ in Thousands	Jul. 31, 2018	Apr. 30, 2018
Inventory, Net [Abstract]
Raw materials	$ 45,737	$ 41,728
Work-in-process	47,192	44,905
Finished goods	36,561	34,111
Total FIFO inventories	129,490	120,744
Reserve to adjust inventories to LIFO value	(15,943)	(15,943)
Total inventories	113,547	$ 104,801
Inventory carried under FIFO	0
Inventory carried under LIFO	$ 0

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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- 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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- Definition

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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- Definition

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

+ References

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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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No definition available.

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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.

+ References

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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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- Definition

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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