Financial Instruments Carried at Fair Value on Recurring Basis (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012		Dec. 31, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives, assets	$ 20.4	[1]	$ 12.6	[1]
Total, assets	20.4		12.6
Derivatives, liabilities	3.9	[1]	6.8	[1]
Contingent consideration arising from acquisitions, liabilities	6.8	[2]	9.1	[2]
Total, liabilities	10.7		15.9
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives, assets	20.4	[1]	12.6	[1]
Total, assets	20.4		12.6
Derivatives, liabilities	3.9	[1]	6.8	[1]
Total, liabilities	3.9		6.8
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration arising from acquisitions, liabilities	6.8	[2]	9.1	[2]
Total, liabilities	$ 6.8		$ 9.1

[1] Represents interest rate swaps and FX forwards on certain assets and liabilities as well as on certain non-U.S. dollar net investments in certain foreign subsidiaries as more fully described in Note 7 to the financial statements

[2] Represents contingent consideration liabilities pursuant to the agreements for certain MA acquisitions which are more fully discussed in Note 8 to the consolidated financial statements