Other Noncurrent Liabilities - Other Noncurrent Liabilities (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Other Liabilities Disclosure [Abstract]
Reserve for uncertain tax positions	$ 41.4	$ 29.4
Asset retirement obligations	25.1	23.8
Insurance claims and expenses	9.8	9.7
Employee benefits	10.9	11.3
Deferred income	1.0	1.0
Other	3.1	3.1
Total	$ 91.3	$ 78.3

Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

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-Section 50

-Paragraph 1

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Total carrying amount of consideration received or receivable as of the balance sheet date representing potential earnings that were not as yet recognized as revenue or other forms of income in conformity with GAAP, and which are expected to be recognized as such after one year or beyond the normal operating cycle, if longer.

+ References

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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The noncurrent portion of the amount recognized for uncertain tax positions as of the balance sheet date.

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The accrued obligation as of the balance sheet date which represents the cost of settling insured claims and insured claims relating to insured events that have occurred but have not yet been reported to the insurer or reinsurer as of the date of the financial statements.

+ References

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-Name Accounting Standards Codification

-Topic 944

-SubTopic 40

-Section 50

-Paragraph 3

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- Definition

Aggregate carrying amount, as of the balance sheet date, of noncurrent obligations not separately disclosed in the balance sheet. Noncurrent liabilities are expected to be paid after one year (or the normal operating cycle, if longer).

+ References

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Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are expected to be paid after one year (or the normal operating cycle, if longer), from the balance sheet date.

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