Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Realized/unrealized embedded derivative, net	$ 206	$ (472)	$ (532)	$ 1,365
Total sales, net	21,098	29,374	49,103	55,952
Dore
Disaggregation of Revenue [Line Items]
Less: Treatment and refining charges	(174)	(61)	(266)	(99)
Total sales, net	11,035	3,700	19,302	5,745
Gold Dore
Disaggregation of Revenue [Line Items]
Total sales, net	10,531	3,110	18,214	4,793
Silver Dore
Disaggregation of Revenue [Line Items]
Total sales, net	678	651	1,354	1,051
Concentrate
Disaggregation of Revenue [Line Items]
Less: Treatment and refining charges	(3,300)	(3,606)	(9,135)	(7,016)
Total sales, net	9,857	26,146	30,333	48,842
Gold Concentrate
Disaggregation of Revenue [Line Items]
Total sales, net	2,467	6,738	8,683	11,303
Silver Concentrate
Disaggregation of Revenue [Line Items]
Total sales, net	2,566	5,542	7,781	9,303
Copper Concentrate
Disaggregation of Revenue [Line Items]
Total sales, net	1,198	2,621	3,559	4,735
Lead Concentrate
Disaggregation of Revenue [Line Items]
Total sales, net	1,750	3,999	5,229	7,394
Zinc Concentrate
Disaggregation of Revenue [Line Items]
Total sales, net	$ 5,176	$ 10,852	$ 14,216	$ 23,123