Goodwill And Other Intangible Assets And Liabilities (Estimated Amortization Expense Relating To Intangible Assets) (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012
Goodwill and Intangible Assets Disclosure [Abstract]
Estimated amortization expense for 2012 (remaining three months)	$ 4.5
Estimated amortization expense for 2013	17.9
Estimated amortization expense for 2014	17.9
Estimated amortization expense for 2015	6.0
Estimated amortization expense for 2016	6.0
Estimated amortization expense for 2017	6.0
Finite-lived intangible assets, total	$ 58.3