Benefit Plans - Amounts Recorded in Consolidated Balance Sheets (Detail) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Non-current liabilities	$ (253.4)	$ (244.6)
U.S. Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Pension and Other Postretirement Defined Benefit Plans, Assets, Noncurrent	0.8	0.5
Current liabilities	(4.4)	(4.1)
Non-current liabilities	(65.3)	(65.6)
Benefit obligations in excess of the fair value of plan assets	(68.9)	(69.2)
Non-US Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Pension and Other Postretirement Defined Benefit Plans, Assets, Noncurrent	3.2	4.5
Current liabilities	(2.9)	(3.0)
Non-current liabilities	(141.4)	(128.3)
Benefit obligations in excess of the fair value of plan assets	(141.1)	(126.8)
Post-retirement
Defined Benefit Plan Disclosure [Line Items]
Pension and Other Postretirement Defined Benefit Plans, Assets, Noncurrent	0.0	0.0
Current liabilities	(3.2)	(3.3)
Non-current liabilities	(33.7)	(35.5)
Benefit obligations in excess of the fair value of plan assets	$ (36.9)	$ (38.8)