Other Income, net (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Other Expense, Net
Unrealized currency exchange (gain) loss	$ (1,560)	$ 14	$ 58	$ (113)
Realized currency exchange loss (gain)	176	21	(115)	172
Unrealized gain from gold and silver rounds/bullion, net	(610)	(226)	(459)	(243)
Other expense (income)	147	84	182	102
Total	$ (1,847)	$ (107)	$ (334)	$ (82)

Unrealized Investment Gains Losses

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

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Amount of income (expense) related to nonoperating activities, classified as other.

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