Supplementary Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Supplementary Cash Flow Information
Unrealized (gain) loss on gold and silver rounds/bullion	$ 151	$ (17)
Unrealized currency exchange (gain) loss	1,618	(127)
Other	11	16
Total other operating adjustments	$ 1,780	$ (128)

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

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