Income Taxes - Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Deferred Tax Assets:
Loss carryforwards	$ 165.5	$ 112.3
Asbestos	118.7	209.8
Employee benefits	70.8	98.9
Accruals	51.3	74.8
Credit carryforwards	5.7	50.7
Other	23.1	21.2
Gross deferred tax assets	435.1	567.7
Less: Valuation allowance	170.0	113.3	$ 135.7	$ 147.1
Net deferred tax assets	265.1	454.4
Deferred Tax Liabilities:
Intangibles	(45.4)	(68.3)
Undistributed earnings	(39.0)	(52.3)
Accelerated depreciation	(31.8)	(36.5)
Investment	(0.2)	(0.4)
Total deferred tax liabilities	(116.4)	(157.5)
Net deferred tax assets	$ 148.7	$ 296.9