Components of Net Periodic Benefit Cost (Detail) - Domestic Retirement Plans - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 32	$ 60	$ 97	$ 136
Interest cost	464	482	1,393	1,446
Recognized net actuarial loss	401	204	1,203	612
Net periodic benefit cost	$ 897	$ 746	$ 2,693	$ 2,194