Retirement Benefits (Components of Net Periodic Benefit Cost for Defined Benefit Plans and Other Postretirement Plans) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 181	$ 214	$ 769	$ 965
Interest cost	788	956	2,282	2,831
Expected return on plan assets	(1,233)	(1,186)	(3,583)	(3,682)
Net amortization	766	906	2,420	2,585
Net periodic benefit cost	502	890	1,888	2,699
Non-U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	331	377	934	1,134
Interest cost	344	437	1,049	1,305
Expected return on plan assets	(203)	(282)	(642)	(838)
Net amortization	241	405	722	1,334
Net periodic benefit cost	713	937	2,063	2,935
Other Postretirement Benefit Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	181	168	494	506
Interest cost	224	208	622	626
Net amortization	(154)	(95)	(462)	(314)
Net periodic benefit cost	$ 251	$ 281	$ 654	$ 818