Inventories (Details) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Average or actual cost (which approximates current costs):
Finished products	$ 230.2	$ 224.4
In-process	2,268.1	1,866.1
Raw materials and supplies	761.4	692.8
Inventory, gross	3,259.7	2,783.3
Less:
Reserve to reduce certain inventories to LIFO basis	(54.1)	(52.7)
Progress payments and advances	(413.8)	(281.2)
Total	$ 2,791.8	$ 2,449.4

Progress payments and advances.

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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.

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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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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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