Other Income (Expense) - Other Income (Expense), Net (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Other Nonoperating Income Expense [Abstract]
Foreign currency transaction gains (losses)	$ (1,645)	$ (1,262)	$ 2,029
Gains (losses) on derivative instruments not designated as hedges	(673)	(674)	(1,751)
Other miscellaneous income (expense)	(40)	(857)	(1,659)
Other income (expense)	(49)	(414)	(2,248)
Other Income (Expense), Net [Member]
Other Nonoperating Income Expense [Abstract]
Net investment gains (losses) on investments held in rabbi trust	$ 2,309	$ 2,379	$ (867)