Other, Net - Other Net in Consolidated Statements of Income (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Other Nonoperating Income Expense [Abstract]
Foreign exchange gain (loss)	$ 374	$ (274)	$ 333	$ 895
Investment income	106	91	309	320
Realized and unrealized gain (loss) on investments	(324)	737	2,806	1,241
Net periodic pension benefit cost	159	(208)	247	(466)
Gain on sale of asset	570		570
Other, net	$ 885	$ 346	$ 4,265	$ 1,990

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

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