CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (DEFICIT) - USD ($) $ in Thousands		Total		Common Stock		Treasury Stock		Additional Paid-in Capital	[1]	Accumulated Deficit	Conversion from Class B common stock	Conversion from Class B common stock Common Stock	Conversion from Class B common stock Additional Paid-in Capital	[1]	Private Placement	Private Placement Common Stock		Private Placement Additional Paid-in Capital	[1]	Sprott Credit Agreement	Sprott Credit Agreement Common Stock	Sprott Credit Agreement Additional Paid-in Capital	[1]	Public Offering Warrants	Public Offering Warrants Common Stock		Public Offering Warrants Additional Paid-in Capital	[1]	2.0 Lien Notes to common stock	[3]	2.0 Lien Notes to common stock Common Stock	[3]	2.0 Lien Notes to common stock Treasury Stock	[3]	2.0 Lien Notes to common stock Additional Paid-in Capital	[1],[3]	2.0 Lien Notes to common stock Accumulated Deficit	[3]	1.5 Lien Notes into common stock	1.5 Lien Notes into common stock Common Stock		1.5 Lien Notes into common stock Additional Paid-in Capital	[1]	1.5 Lien Notes into common stock Accumulated Deficit	1.25 Lien Notes into common stock	1.25 Lien Notes into common stock Common Stock	1.25 Lien Notes into common stock Additional Paid-in Capital	[1]
Beginning balance (in shares) at Dec. 31, 2018	[1]			307,831		17,927
Beginning balance at Dec. 31, 2018		$ (340,356)		$ 0	[1]	$ 0	[1]	$ 5,187		$ (345,543)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	[1]			37,600
Share repurchased (in shares)	[1]					4,176
Net loss		(98,895)								(98,895)
Ending balance (in shares) at Dec. 31, 2019	[1]			345,431		22,103
Ending balance at Dec. 31, 2019		(439,251)	[2]	$ 0	[1]	$ 0	[1]	5,187		(444,438)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued upon conversion (in shares)	[1]											4,813,180																			14,795,153		(22,103)							16,025,316						4,845,920
Shares issued upon conversion											$ 25,000		$ 25,000																$ 220,859		$ 2	[1]			$ 146,217		$ 74,640		$ 145,685	$ 2	[1]	$ 160,252		$ (14,569)	$ 48,459		$ 48,459
Shares issued (in shares)	[1]			101												7,596,309					496,634				9,583,334
Shares issued		1						1							$ 75,963	$ 1	[1]	$ 75,962		$ 6,282		$ 6,282		$ 83,514	$ 1	[1]	$ 83,513
Unredeemed SPAC shares of MUDS public stockholders (in shares)	[1]			1,197,704
Unredeemed SPAC shares of MUDS public stockholders		3,723						3,723
Common shares issued to underwriter (in shares)	[1]			44,395
Common shares issued to underwriter		444						444
Vesting of restricted stock	[4]	1,802						1,802
Equity issuance costs		(8,255)						(8,255)
Stock-based compensation costs		388						388
Shares issued under stock-based compensation program (in shares)	[1]			157,829
Net loss		(132,670)								(132,670)
Ending balance (in shares) at Dec. 31, 2020	[1]			59,901,306		0
Ending balance at Dec. 31, 2020		$ 31,944	[2]	$ 6	[1]	$ 0	[1]	$ 548,975		$ (517,037)

[1] Retroactively restated for the reverse recapitalization as described in Note 2 - Summary of Significant Accounting Policies.

[2] Retroactively restated for the reverse recapitalization as described in Note 2 - Summary of Significant Accounting Policies.

[3] Includes 3,511,820 shares of HYMC common stock received by Seller that were surrendered by the Company.

[4] As of December 31, 2020 there were 21,256 unissued shares underlying restricted stock units that had vested.