Supplementary Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Supplementary Cash Flow Information
Unrealized loss (gain) on gold and silver rounds/bullion			$ (459)	$ (243)
Unrealized foreign currency exchange gain	$ (1,560)	$ 14	58	(113)
Other			33	63
Total other operating adjustments			$ (368)	$ (293)

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

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