Pension and Other Postretirement Benefits - Schedule of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Pension Plan [Member] | U.S. Defined Benefit Pension Plans [Member] | U.S. [Member]
Accumulated other comprehensive loss:
Net actuarial loss (gain)	$ 47,252	$ 48,153
Prior service cost (credit)	156	209
Total	47,408	48,362
Defined Benefit Pension Plan [Member] | Foreign Pension Benefits [Member]
Accumulated other comprehensive loss:
Net actuarial loss (gain)	25,914	25,547
Prior service cost (credit)	(9,174)	0
Total	16,740	25,547
Other Postretirement Benefit Plans [Member]
Accumulated other comprehensive loss:
Net actuarial loss (gain)	(1,211)	936
Prior service cost (credit)	(13,809)	(15,581)
Total	$ (15,020)	$ (14,645)