Debt - Summary of Debt Instruments (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Short-term debt
Senior Notes due	$ 250.0
Long-term debt
Other long-term debt	4.0	2.1
Debt discount	(1.5)	(1.5)
Adjustment related to interest rate swaps	16.3	9.3
Total long-term debt	1,426.4	1,672.3
Senior Notes due 2014 [Member]
Short-term debt
Senior Notes due	250.0
Long-term debt
Senior Notes due		250.0
Senior Notes due 2019 [Member]
Long-term debt
Senior Notes due	500.0	500.0
Senior Notes due 2021 [Member]
Long-term debt
Senior Notes due	300.0	300.0
Senior Notes due 2039 [Member]
Long-term debt
Senior Notes due	500.0	500.0
Japan [Member]
Long-term debt
Japan term loan	$ 107.6	$ 112.4

Face (par) amount of debt instrument at time of issuance.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher FASB

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Including both current and noncurrent portions, carrying amount as of the balance sheet date of other forms of debt not elsewhere specified in the taxonomy with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

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Carrying value as of the balance sheet date of the portion of long-term notes having the highest claim on the assets of the issuer in case of bankruptcy or liquidation, due within one year or the normal operating cycle, if longer. Senior note holders are paid off in full before any payments are made to debt holders having a lesser priority of repayment.

+ References

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

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Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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- Definition

Change in fair value of debt hedged by interest rate swaps.

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No definition available.

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