Inventories (Schedule of Inventories) (Details) - USD ($) $ in Thousands	Aug. 31, 2019	Aug. 31, 2018
Inventory Disclosure [Abstract]
Raw materials and supplies	$ 49,047	$ 36,316
Work in process	4,514	9,176
Finished goods and purchased parts	46,812	40,197
Total inventory value before LIFO adjustment	100,373	85,689
Less adjustment to LIFO value	(8,086)	(6,456)
Inventories, net	$ 92,287	$ 79,233

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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.

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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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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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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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