Prepaids and Other - Components of prepaids (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid insurance	$ 3,611	$ 1,847
Mining claims and permitting fees	1,255	417
Subscription and license fees	176	259
Equipment mobilization	0	423
Other	87	252
Prepaids	$ 5,129	$ 3,198

Amount of asset related to consideration paid in advance for insurance that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

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Name:	us-gaap_PrepaidInsurance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant