Components of Net Periodic Benefit Cost for Defined Benefit Plans and Other Postretirement Plans (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
U.S. Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 1,162	$ 1,526	$ 1,756
Interest cost	4,037	3,766	4,247
Expected return on plan assets	(5,430)	(5,318)	(4,687)
Net amortization	2,187	7,621	5,376
Net periodic benefit cost	1,956	7,595	6,692
Non-U.S. Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	1,331	1,388	1,300
Interest cost	2,345	2,146	2,206
Expected return on plan assets	(1,297)	(1,055)	(1,035)
Net amortization	1,400	955	589
Net periodic benefit cost	3,779	3,434	3,060
Other Postretirement Benefit Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	714	968	763
Interest cost	932	906	922
Net amortization	(474)	24	11
Net periodic benefit cost	$ 1,172	$ 1,898	$ 1,696