Revenues - Disaggregation of revenue (Details) $ in Thousands	3 Months Ended
Mar. 31, 2022 USD ($) oz	Mar. 31, 2021 USD ($) oz
Disaggregation of Revenue [Line Items]
Revenues	$ 9,166	$ 19,036
Gold sales
Disaggregation of Revenue [Line Items]
Revenues	$ 8,906	$ 17,541
Ounces Sold \| oz	4,773	9,830
Silver sales
Disaggregation of Revenue [Line Items]
Revenues	$ 260	$ 1,495
Ounces Sold \| oz	10,934	57,236

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details