Inventories (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2011	Jun. 30, 2011
Inventories
Finished goods	$ 327,038	$ 303,716
Work in process and powder blends	240,543	202,940
Raw materials and supplies	114,980	109,683
Inventories at current cost	682,561	616,339
Less: LIFO valuation	(123,036)	(96,366)
Total inventories	$ 559,525	$ 519,973
Inventories (Textual) [Abstract]
Percentage of inventories valued by using LIFO method	50.00%	50.00%

Inventories.

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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.

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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

Reflects the difference between (a) inventory at the lower of LIFO cost or market and (b) inventory at replacement cost or at the lower of some acceptable inventory accounting method (such as FIFO or average cost), or market. If material, reflects an excess of replacement or current cost over stated LIFO value parenthetically on the balance sheet or in a note to the financial statements.

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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).

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- Definition

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

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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.

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The percentage of LIFO (last in first out) inventory to total inventory as of the balance sheet date if other than 100 percent.

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