Other, Net - Other Net in Consolidated Statements of Income (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Other Nonoperating Income Expense [Abstract]
Foreign exchange gains	$ 600	$ 1,053
Investment income	97	139
Realized and unrealized gains on investments	2,404	97
Net periodic benefit cost	44	(129)
Other, net	$ 3,145	$ 1,160

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

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