Inventories (Schedule Of Inventories) (Details) (USD $) In Thousands, unless otherwise specified	Feb. 28, 2015	Aug. 31, 2014	Feb. 28, 2014
Inventories [Abstract]
Raw materials and supplies	$ 24,724	$ 19,953	$ 19,614
Work in process	7,421us-gaap_InventoryWorkInProcess	9,990us-gaap_InventoryWorkInProcess	7,722us-gaap_InventoryWorkInProcess
Finished goods and purchased parts	57,472us-gaap_InventoryFinishedGoods	48,300us-gaap_InventoryFinishedGoods	59,928us-gaap_InventoryFinishedGoods
Total inventory value before LIFO adjustment	89,617us-gaap_InventoryGross	78,243us-gaap_InventoryGross	87,264us-gaap_InventoryGross
Less adjustment to LIFO value	(7,354)us-gaap_InventoryLIFOReserve	(6,547)us-gaap_InventoryLIFOReserve	(6,270)us-gaap_InventoryLIFOReserve
Inventories, net	$ 82,263us-gaap_InventoryNet	$ 71,696us-gaap_InventoryNet	$ 80,994us-gaap_InventoryNet

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a)(1))

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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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- Definition

Amount of difference between inventory at lower of LIFO cost or market and inventory at lower of other inventory accounting method cost or market, for example, but not limited to, FIFO or average cost.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Subparagraph (SX 210.5-02.6(a))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 330

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

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-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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