Restructuring Charges - Schedule of Restructuring Activities (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended				12 Months Ended	6 Months Ended	12 Months Ended		6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 Lease And Exit Costs [Member]	Jun. 30, 2013 Two Thousand Twelve Restructuring [Member]	Dec. 31, 2012 Two Thousand Twelve Restructuring [Member]	Jun. 30, 2013 Two Thousand Twelve Restructuring [Member] Employee Severance and other Personnel Benefits [Member]	Dec. 31, 2012 Two Thousand Twelve Restructuring [Member] Employee Severance and other Personnel Benefits [Member]		Jun. 30, 2013 Two Thousand Twelve Restructuring [Member] Other Restructuring Costs [Member]	Dec. 31, 2012 Two Thousand Twelve Restructuring [Member] Other Restructuring Costs [Member]	Jun. 30, 2013 Restructuring Charges [Member] Two Thousand Twelve Restructuring [Member]	Dec. 31, 2012 Restructuring Charges [Member] Two Thousand Twelve Restructuring [Member]
Restructuring Reserve [Roll Forward]
Restructuring cost, beginning balance			$ 19.2		$ 0.3			$ 18.0			$ 0.9
(Income) expense, net	3.1	0	3.3	0	0	3.6	24.1	2.5	18.4	[1]	0.8	2.3	3.3	20.7
Restructuring reserve, translation adjustment			(0.4)		0			(0.4)			0
Cash utilized, net			(13.2)		(0.2)	(13.2)	(3.8)	(11.3)			(1.7)
Non utilized, net			0		0			0			0
Restructuring cost, ending balance	$ 8.9		$ 8.9		$ 0.1			$ 8.8	$ 18.0		$ 0	$ 0.9

[1] Included within the $18.4 million of employee severance and other personnel benefits is a net pension curtailment gain of $1.5 million recognized in the year ended December 31, 2012.