Other, Net - Other Net in Consolidated Statements of Income (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Other Nonoperating Income Expense [Abstract]
Foreign exchange gains	$ 368	$ 476	$ 139	$ 1,467
Investment income	230	119	725	287
Realized and unrealized (losses) gains on investments	(264)	2,094	2,497	2,169
Net periodic pension benefit cost	368	(60)	845	(119)
Other, net	$ 702	$ 2,629	$ 4,206	$ 3,804

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

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