Other, Net - Other Net in Consolidated Statements of Income (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Other Nonoperating Income Expense [Abstract]
Foreign exchange gain	$ 476	$ 374	$ 1,467	$ 333
Investment income	119	106	287	309
Realized and unrealized gain (loss) on investments	2,094	(324)	2,169	2,806
Net periodic pension benefit cost	(60)	159	(119)	247
Gain on sale of asset		570		570
Other, net	$ 2,629	$ 885	$ 3,804	$ 4,265