Inventories (Schedule of Inventories) (Details) - USD ($) $ in Thousands	Feb. 28, 2019	Aug. 31, 2018	Feb. 28, 2018
Inventory Disclosure [Abstract]
Raw materials and supplies	$ 47,573	$ 36,316	$ 38,716
Work in process	8,715	9,176	9,371
Finished goods and purchased parts	51,910	40,197	60,925
Total inventory value before LIFO adjustment	108,198	85,689	109,012
Less adjustment to LIFO value	(8,214)	(6,456)	(6,037)
Inventories, net	$ 99,984	$ 79,233	$ 102,975

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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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