Acquisitions and Divestitures (Pro Forma Information) (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Business Combinations [Abstract]
Revenue (As reported)	$ 6,059.5	$ 5,808.2
Net income applicable to common shareholders (As reported)	4.0	54.5
Earnings per common share - assuming dilution (As reported)	$ 0.08	$ 1.02
Revenue (Pro Forma)	6,804.3	6,776.8
Net income applicable to common shareholders (Pro forma)	$ 22.7	$ 54.0
Earnings per common share - assuming dilution (Pro forma)	$ 0.44	$ 1.01

Business combination, pro forma information, earnings per share, diluted , actual.

No definition available.

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- Definition

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

+ Details

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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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