Changes in Level 3 Liabilities (Detail) (Contingent Consideration, USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013
Contingent Consideration
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value Liabilities Beginning Balance	$ 55.4		$ 50.1
Total (Gains) and Losses:
Included in Earnings	(0.1)	[1]	5.3	[1]
Purchases, Issuances, Sales, and Settlements:
Settlements	(55.3)
Fair Value Liabilities Ending Balance			55.4
Unrealized (Gains) Losses Included in Earnings Related to Financial Instruments Held at December 31			$ 5.3	[1]

[1] Gains (losses) are recorded in other operating income (expense) within the consolidated statement of income.