Property Plant and Equipment (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]
Land and land improvements		$ 98.3	$ 100.5
Buildings and leasehold improvements		203.4	195.4
Machinery, equipment and other		339.6	311.0
Construction in progress		7.1	15.7
Total	648.4	648.4	622.6
Less: Accumulated depreciation	(174.1)	(165.0)	(131.5)
Net property, plant and equipment	$ 474.3	$ 483.4	$ 491.1

The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.

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- Definition

Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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- Definition

Gross amount, at the balance sheet date, of long-lived assets under construction that include construction costs to date on capital projects that have not been completed and assets being constructed that are not ready to be placed into service.

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- Definition

Carrying amount of real estate held for productive use and alterations to land which improves its potential for use, examples include, but are not limited to, walkways, driveways, fences, and parking lots. Excludes land held for sale.

+ References

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Gross amount, as of the balance sheet date, of long-lived, depreciable assets used in the production process to produce goods and services.

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Gross amount of long-lived physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

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Amount, net of accumulated depreciation, depletion and amortization, of long-lived physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 7

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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