Income Taxes - Components of Comprehensive Provision for Income Taxes Allocation (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Schedule Of Income Tax [Line Items]
Expected tax expense (benefit) at U.S. federal statutory income tax rate of 35%	$ 13.9	$ (10.7)
Incremental net tax on earnings and losses of non-U.S. and U.S. subsidiaries	11.2	2.4
Non-U.S. tax rates	(2.4)	0.2
Valuation allowance	(5.0)
Adjustment to the reserve for uncertain tax positions, net	0.5	0.2
Nondeductible expenses	0.5	0.1
Domestic production activities deduction	(0.6)	(0.3)
U.S. state income taxes and other, net	(0.1)	(0.5)
Income tax expense (benefit)	18.0	(8.6)
Comprehensive provision for income taxes allocable to:
Net income (loss)	18.0	(8.6)
Other comprehensive income (loss):
Marketable securities	(0.2)	(0.2)
Currency translation	1.7	2.8
Interest rate swap	0.4	(2.1)
Total	20.7	(7.5)
Pension Plans
Other comprehensive income (loss):
Defined benefit plans	0.9	0.8
OPEB Plans
Other comprehensive income (loss):
Defined benefit plans	$ (0.1)	$ (0.2)