Basis of Presentation - Additional Information (Details) - Surety Bond $ in Millions	Nov. 06, 2020 USD ($)
Debt Instrument [Line Items]
Transaction support agreements, percentage of Participating Sureties	99.00%
Transaction support agreements, additional collateral to be posted	$ 75.0
Debt instrument, transaction support agreements, fair value of second liens on mining equipment	200.0
Transaction support agreements, additional collateral to be posted per year through 2025	25.0
Transaction support agreements, additional collateral term, free cash flow in any twelve-month period	100.0
Transaction support agreements, additional collateral term, sale of assets benchmark (in excess of)	$ 10.0