Nature of Business (Details)	Dec. 31, 2018 a
Mineral Properties [Line Items]
Area of mining claims	9,358
Daney Ranch (Land and buildings)
Mineral Properties [Line Items]
Area of land (in acres)	98
Area of water rights (in acres)	203
Private Lands
Mineral Properties [Line Items]
Area of mining claims	2,396
Bureau of Land Management Lands
Mineral Properties [Line Items]
Area of mining claims	6,962