Retirement Benefit Plans - Reconciliation of Beginning and Ending Balances of Foreign Pension Plan Assets Measured at Fair Value (Detail) - Foreign-based Defined Benefit Plans [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Schedule of Fair Values of Plan Assets [Line Items]
Plan assets at fair market value - beginning of year	$ 505.6	$ 385.4
Translation loss	(40.4)	(12.3)
Plan assets at fair market value - end of year	507.0	505.6
Fair Value Measurements at Reporting Date Using: Significant Unobservable Inputs (Level 3) [Member]
Schedule of Fair Values of Plan Assets [Line Items]
Plan assets at fair market value - beginning of year	73.9
Gains on assets sold	0.1
Change in fair value of assets	2.7
Net purchases and sales	5.0
Translation loss	(3.0)
Plan assets at fair market value - end of year	$ 78.7	$ 73.9