Pension and Other Postretirement Benefits - Amounts Included in Accumulated Other Comprehensive Loss to be Recognized over Next Year (Detail) $ in Thousands	Dec. 31, 2017 USD ($)
Defined Benefit Pension Plan [Member] | U.S. Defined Benefit Pension Plans [Member] | U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain)	$ 1,763
Prior service cost (credit)	52
Total amounts included in accumulated other comprehensive loss to be recognized over next year	1,815
Defined Benefit Pension Plan [Member] | Foreign Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain)	784
Prior service cost (credit)	(324)
Total amounts included in accumulated other comprehensive loss to be recognized over next year	460
Other Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain)	(109)
Prior service cost (credit)	(1,607)
Total amounts included in accumulated other comprehensive loss to be recognized over next year	$ (1,716)