Income Taxes - Components of Net Deferred Tax Liability (Detail) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Tax effect of temporary differences related to:
Inventories	$ 3.7	$ 5.4
Accrued OPEB costs	4.0	4.8
Accrued pension costs	44.0	52.0
Currency revaluation on intercompany debt	18.6	5.6
Accrued environmental liabilities	39.9	38.8
Other deductible differences	45.7	34.7
Tax loss and tax credit carryforwards	154.3	163.6
Valuation allowance	(168.9)	(0.1)
Adjusted gross deferred tax assets (liabilities)	141.3	304.8
Netting of items by tax jurisdiction, assets	(140.0)	(143.9)
Net noncurrent deferred tax asset (liability)	1.3	160.9
Tax effect of temporary differences related to:
Inventories	(3.7)	(5.2)
Marketable securities	(98.2)	(126.4)
Property and equipment	(96.6)	(109.2)
Other taxable differences	(21.7)	(21.6)
Investments in subsidiaries and affiliates	(238.8)	(278.7)
Tax on unremitted earnings of non-U.S. subsidiaries	(2.0)	(2.6)
Adjusted gross deferred tax assets (liabilities)	(461.0)	(543.7)
Netting of items by tax jurisdiction, liabilities	(140.0)	143.9
Net noncurrent deferred tax asset (liability)	$ (321.0)	$ (399.8)