Other, Net - Other Net in Consolidated Statements of Income (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Other Nonoperating Income Expense [Abstract]
Foreign exchange gain (loss)	$ (641)	$ 116	$ (41)	$ 1,169
Investment income	106	90	203	229
Realized and unrealized gains on investments	726	407	3,130	504
Net periodic pension benefit cost	44	(129)	88	(258)
Other, net	$ 235	$ 484	$ 3,380	$ 1,644

Amount of net periodic benefit cost (credit) for defined benefit plan.

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