Acquisitions and Divestitures (Details) (USD $) In Millions	9 Months Ended	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 Construction Products Group [Member]	Sep. 30, 2011 Construction Products Group [Member]
Acquisitions:
Purchase price			$ 32.8	$ 56.4
Net cash paid	42.5	46.9	27.2	42.5
Goodwill recorded			22.3	29.3
Divestitures:
Proceeds			0	8.3
Gain recognized			0	0.7
Goodwill charged off			$ 0	$ 1.0

Business acquisition cost of acquired entity.

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The gain (loss) resulting from the sale of a disposal group that is not a discontinued operation. It is included in income from continuing operations before income taxes in the income statement.

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The aggregate amount of goodwill acquired in the period and allocated to the reportable segment. The value is stated at fair value based on the purchase price allocation.

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Write-off of the carrying amount of goodwill associated with all or a portion of a reporting unit that is sold in the period.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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This element represents the cash inflow during the period from the sale of a component of the entity.

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