Goodwill and Other Identifiable Intangible Assets - Estimated Future Amortization Expense for Identifiable Intangible Assets (Detail) $ in Millions	Dec. 31, 2015 USD ($)
Expected Amortization Expense
Estimated amortization expense 2016	$ 149.5
Estimated amortization expense 2017	148.0
Estimated amortization expense 2018	145.6
Estimated amortization expense 2019	138.8
Estimated amortization expense 2020	$ 133.7