Fair Value Measurements - Narrative (Details)								1 Months Ended		3 Months Ended			9 Months Ended		14 Months Ended
	Sep. 29, 2020 USD ($) $ / shares shares	Sep. 08, 2020 USD ($) $ / shares	Sep. 01, 2020	Jul. 22, 2020 shares	May 22, 2020 USD ($) $ / shares shares	Apr. 24, 2020	Jul. 18, 2019 USD ($) shares	Apr. 30, 2020	Jan. 31, 2018	Sep. 30, 2020 USD ($) $ / shares shares	Jun. 30, 2020 USD ($) shares	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) $ / shares shares	Sep. 30, 2019 USD ($)	Sep. 30, 2019 shares	May 15, 2020 shares	Mar. 20, 2020 USD ($) $ / shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 30, 2019 USD ($)	Dec. 19, 2019 USD ($)	Nov. 18, 2019 USD ($)	Oct. 14, 2019 USD ($)	Aug. 30, 2019 USD ($)	Jun. 30, 2019 shares	May 31, 2019 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Issuance of convertible preferred stock										$ 0			$ 0					$ 0
Change in estimated fair value of Tonogold shares										$ (53,610)		$ (332,263)	1,282,319	$ (332,263)
Convertible preferred stock exchanged, amount													$ 3,900,000
Tonogold preferred shares (in shares) | shares										0			0					0						1,274
Common shares of Tonogold (in shares) | shares				2,040,483						34,440,766			34,440,766					27,236,489
Number of shares sold (in shares) | shares				2,040,483						3,450,138					2,327,400
Common stock, shares outstanding (in shares) | shares										34,440,766			34,440,766					27,236,489
Principal amount		$ 4,475,000
Interest rate		12.00%
Notes receivable at fair value		$ 6,100,000								$ 6,400,000			$ 6,400,000
Change in estimated fair value of contingent asset										647,502		0	(765,880)	0
Stock based investment										100,000			100,000					$ 0
Make-whole liability										0	$ 384,873		0
Long-term debt at fair value										4,800,000			4,800,000					5,400,000
Pelen LLC
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Membership interest						25.00%		25.00%	25.00%
Other Income
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in estimated fair value of contingent asset										(300,000)			(300,000)
Tonogold Resources, Inc.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Issuance of convertible preferred stock										$ 6,100,000			$ 6,100,000					6,100,000
Convertible Debt
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate																	12.00%
Convertible Debt | Tonogold Resources, Inc.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Principal amount		4,475,000															$ 5,475,000
Private Placement Conversion Price
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input | $ / shares										0.18			0.18
Percentage of 20-Day Volume-Weighted Closing Price
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input					0.85
Tonogold Resources, Inc.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Closing stock price (in dollars per share) | $ / shares	$ 0.18				$ 0.18					$ 0.39			$ 0.39
Issuance of convertible preferred stock					$ 7,600,000					$ 2,600,000			$ 2,600,000					6,100,000	$ 100,000	$ 500,000	$ 7,600,000	$ 750,000	$ 830,000		$ 3,920,000
Change in estimated fair value of Tonogold shares										$ (2,500,000)		$ (300,000)	$ (2,500,000)	$ (300,000)
Convertible preferred stock exchanged, amount	$ 2,820,000				$ 1,100,000
Tonogold preferred shares (in shares) | shares	2,820				1,100
Common shares of Tonogold (in shares) | shares	15,666,667				6,111,111					21,777,778			21,777,778
Number of shares sold (in shares) | shares													3,557,209
Common stock, shares outstanding (in shares) | shares										18,220,569			18,220,569
Notes receivable at fair value		$ 6,141,497
Change in estimated fair value of contingent asset													$ (300,000)
Estimated fair value percentage										1.20			1.20
Tonogold Resources, Inc. | Convertible Debt
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Principal amount																	$ 5,475,000
Interest rate		12.00%
Tonogold Resources, Inc. | Convertible Debt | Change Of Control, Redemption Right
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Redemption price percentage		125.00%
Tonogold Resources, Inc. | Convertible Debt | Default Redemption Right
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Redemption price percentage		118.00%
Tonogold Resources, Inc. | Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Issuance of convertible preferred stock																		$ 7,600,000
Tonogold Resources, Inc. | Common Share Price
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input | $ / shares		0.35								0.39			0.39				0.35
Tonogold Resources, Inc. | Volatility
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input		0.96								0.96			0.96				0.960
Tonogold Resources, Inc. | Risk-Free Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input		0.0015								0.0015			0.0015				0.0015
Tonogold Resources, Inc. | Cost of Debt
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input		0.1112								0.1112			0.1112				0.1112
Tonogold Resources, Inc. | Private Placement Conversion Price
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input | $ / shares		0.30								0.30			0.30				0.300
Tonogold Resources, Inc. | Probability of Prepayment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input | $ / shares		0.05								0.05			0.05				0.05
Tonogold Resources, Inc. | Probability of Change in Control
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input		0.05								0.05			0.05				0.05
Tonogold Resources, Inc. | Probability of Default
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input		0.27								0.27			0.27				0.27
Pelen LLC
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Closing stock price (in dollars per share) | $ / shares																		$ 0.47
Pelen LLC | Pelen LLC
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Membership interest			75.00%
MCU
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Closing stock price (in dollars per share) | $ / shares										$ 1.08			$ 1.08
Number of shares sold (in shares) | shares											900,000
Stock based investment										$ 850,000			$ 850,000
Net proceeds from common stock							$ 500,000				$ 465,127
Mercury Clean Up LLC
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Make-whole liability										$ 0			$ 0					$ 452,740
Joint venture, common stock issued (in shares) | shares							900,000									625,000