Miscellaneous Income (Expense), Net - Components of Miscellaneous Income (Expense), Net (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Other Income And Expenses [Abstract]
Net gain (loss) on foreign-currency transactions	$ 386	$ (1,004)	$ (660)
Other income	674	650	237
Miscellaneous income (expense), net	$ 1,060	$ (354)	$ (423)

Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

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