Goodwill and Intangible Assets - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Goodwill and Intangible Assets Disclosure [Line Items]
Number of reporting units	7
Cash flows discounted range lower limit	7.00%
Cash flows discounted range upper limit	10.00%
Impairments of finite-lived identifiable intangible assets	$ 1.5	$ 0.4	$ 0.3
Amortization of intangible assets	21.0	9.0	10.6
Estimated future amortizatiof expense of intangible assets for 2012	45.0
Estimated future amortizatiof expense of intangible assets for 2013	43.7
Estimated future amortizatiof expense of intangible assets for 2014	43.0
Estimated future amortizatiof expense of intangible assets for 2015	42.9
Estimated future amortizatiof expense of intangible assets for 2016	$ 42.5