Inventories, net - Schedule of inventory, Ore on leach pads (Details) $ in Thousands	Jun. 30, 2021 USD ($) oz	Dec. 31, 2020 USD ($) oz
Amount
Ore on leach pads, current | $	$ 37,664	$ 38,041
Ore on leach pads, non-current | $	7,298	7,243
Total | $	$ 44,962	$ 45,284
Gold Ounces
Ore on leach pads, current | oz	21,723	21,869
Ore on leach pads, non-current | oz	4,209	4,164
Total | oz	25,932	26,033