Defined Contribution Plans, Pension and Other Post-Retirement Benefit Plans - Amounts Recognized as Other Changes in Plan Assets and Benefit Obligations in Other Comprehensive Income (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Other Postretirement Benefit Plans | U.S. Pension and Other Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Actuarial loss (gain)	$ 1,266	$ (1,087)
Amortization of actuarial (gain) loss	(263)	(367)
Prior service credit	(6)	(6)
Total recognized in other comprehensive income (loss)	997	(1,460)
Pension Plans | Non-U.S. Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Actuarial loss (gain)	245	519
Amortization of actuarial (gain) loss	781	(504)
Prior service credit	(491)	0
Total recognized in other comprehensive income (loss)	$ 535	$ 15