Other, Net - Other Net in Consolidated Statements of Income (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Other Nonoperating Income Expense [Abstract]
Foreign exchange gain (loss)	$ 423	$ (641)	$ 991	$ (41)
Investment income	93	106	168	203
Realized and unrealized gains on investments	3,950	726	75	3,130
Net periodic pension benefit cost	(29)	44	(59)	88
Other, net	$ 4,437	$ 235	$ 1,175	$ 3,380

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

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