Unrecognized Tax Benefits (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Taxes [Line Items]
Balance at beginning of year	$ 76.4	$ 157.1	$ 176.4
Additions for tax positions of the current year	6.3	6.1	10.2
Additions for tax positions of prior years	3.9	6.0	9.5
Reductions for tax positions of prior years	(29.6)	(26.9)	(18.1)
Settlements during the year	(5.6)	(3.3)	(9.6)
Lapses of applicable statutes of limitations	(3.5)	(62.3)	(13.6)
Foreign exchange and other		(0.3)	2.3
Balance at end of year	$ 47.9	$ 76.4	$ 157.1