Schedule of Inventories (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Schedule of Inventory [Line Items]
Raw materials, including parts and subassemblies	$ 278,855	$ 256,055
Work-in-process	49,938	44,417
Finished goods	62,994	62,230
Inventories, gross	391,787	362,702
Excess of FIFO costs over LIFO costs	(19,569)	(19,505)
Inventories, net	$ 372,218	$ 343,197

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Amount before last-in first-out (LIFO) and valuation reserves of merchandise or goods held by the entity 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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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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Gross amount 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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