Investments in Affiliated Companies - Operating Results of Affiliated Companies of Parent (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Revenues	$ 163.2	$ 165.9	$ 506.4	$ 502.0
Pre-tax income reported by affiliates	$ 40.2	$ 6.7	$ 41.6	$ 89.2

The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.

No definition available.

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