Inventories Table (Detail) (Truck, Parts and Other, USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Truck, Parts and Other
Inventory [Line Items]
Finished products	$ 512.3	$ 440.6
Work in process and raw materials	587.7	545.2
Inventory, Gross, Total	1,100.0	985.8
Less LIFO reserve	(174.3)	(172.2)
Inventories, net	$ 925.7	$ 813.6

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

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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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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.

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The aggregate carrying amount as of the balance sheet date of items held by the entity which are partially completed at the time of measurement and unprocessed items that will go through the production process and become part of the final product. Includes supplies used directly or indirectly in the manufacturing or production process. This element may be used when the reporting entity combines work in process and raw materials into an aggregate amount.

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

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