Long-term Reclamation Liability and Retirement Obligation Asset (Reconciliation of Aggregate Retirement Liability) (Details) - USD ($) |
12 Months Ended | ||
---|---|---|---|
Apr. 30, 2019 |
Dec. 31, 2019 |
Dec. 31, 2018 |
|
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] | |||
Long-term reclamation liability — beginning of year | $ 7,441,091 | $ 7,417,680 | |
Reduction of obligation | $ (400,000) | (410,018) | 0 |
Amount reclassified to liabilities held for sale | (1,019,705) | 0 | |
Accretion of reclamation liability | 22,840 | 23,411 | |
Long-term reclamation liability — end of year | $ 6,034,208 | $ 7,441,091 |