Inventories (Schedule Of Major Classifications Of Inventories) (Details) (USD $) In Thousands	Oct. 31, 2011	Jul. 31, 2011
Inventories [Abstract]
Raw materials	$ 101,910	$ 104,360
Chassis	39,154	46,548
Work in process	50,162	48,575
Finished goods	21,063	14,179
Total	212,289	213,662
Excess of FIFO costs over LIFO costs	(29,164)	(29,164)
Total inventories	$ 183,125	$ 184,498

Carrying amount as of balance sheet date of major components of certain assembled products.

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- Definition

The excess of replacement or current cost over the stated LIFO (last in first out) inventory value when the LIFO inventory method is utilized.

+ References

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- Definition

Carrying amount as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

+ References

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-Name Regulation S-X (SX)

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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

+ Details

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- Definition

Carrying amount (lower of cost or market) as of the balance sheet date of inventories less all valuation and other allowances. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer).

+ References

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- Definition

Carrying amount as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process. Also includes purchased parts that will be used as components of a finished product.

+ References

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

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- Definition

Carrying amount as of the balance sheet date of merchandise or goods which are partially completed, are generally comprised of raw materials, labor and factory overhead costs, and which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

+ References

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