Income Taxes - Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Deferred Tax Assets And Liabilities [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Foreign (jurisdictions with unlimited tax loss carryforward periods)	$ 1,763.9
Deferred tax assets
Accrued liabilities and reserves	41.9	$ 42.9
Pension and other post-retirement compensation and benefits	25.2	25.2
Employee compensation and benefits	19.6	21.8
Tax loss and credit carryforwards	712.0	724.7
Interest limitations	45.0	20.6
Total deferred tax assets	843.7	835.2
Valuation allowance	693.8	711.9
Deferred tax assets, net of valuation allowance	149.9	123.3
Deferred tax liabilities
Property, plant and equipment	8.5	7.1
Goodwill and other intangibles	200.4	179.7
Other liabilities	15.8	16.2
Deferred Tax Liabilities, Gross	224.7	203.0
Total deferred tax liabilities	74.8	$ 79.7
Deferred Tax Assets, Operating Loss Carryforwards, Not Subject to Expiration	$ 14.6