Acquisitions and Dispositions - Pro Forma Results Narrative (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Business Combinations [Abstract]
Pro forma amortization of purchased intangibles	$ 19.9	$ 21.2	$ 60.8	$ 64.0
Pro forma restructuring and impairment Charges	$ 13.6	$ 47.1	$ 61.5	$ 111.9