Company's Warranty Liability Activity (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended	6 Months Ended
	May 05, 2011	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Product Warranties [Abstract]
Balance at January 1			$ 131.9	$ 112.1
Expense			30.3	38.1
Net increase in warranty reserve due to settlement	7.5	8.2		7.5
Claims settled			(30.2)	(27.7)
Balance at June 30		$ 130.0	$ 132.0	$ 130.0