Property, Plant and Equipment (Details)					1 Months Ended		3 Months Ended		9 Months Ended	12 Months Ended
	Aug. 08, 2016 USD ($) item	Aug. 02, 2016 USD ($) shares	Apr. 28, 2016 USD ($)	Apr. 18, 2016 USD ($)	Feb. 28, 2017 USD ($)	Oct. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2016 USD ($) shares	Dec. 31, 2015 USD ($)	Sep. 29, 2015 USD ($)
Property, plant and equipment
Property, plant and equipment, gross										$ 34,751,000	$ 35,849,000
Less: Accumulated depreciation & amortization										(25,516,000)	(24,724,000)
Property, plant and equipment, net										9,235,000	11,125,000
Gain on sale of equipment										1,791,000	719,000
Proceeds from sale of assets										1,167,000	789,000
Related party receivable										643,000
Payments to acquire property										50,000	44,000
Impairment of long lived assets										0	13,181,000
Sale, not discontinued operations
Property, plant and equipment
Gain on sale of equipment											200,000
Sale, not discontinued operations | Equipment sale
Property, plant and equipment
Proceeds from sale of assets											500,000
Mineral properties
Property, plant and equipment
Property, plant and equipment, gross										9,352,000	9,630,000
Exploration properties
Property, plant and equipment
Property, plant and equipment, gross										2,518,000	2,518,000
Royalty properties
Property, plant and equipment
Property, plant and equipment, gross										200,000	200,000
Buildings
Property, plant and equipment
Property, plant and equipment, gross										4,386,000	4,377,000
Mining equipment and machinery
Property, plant and equipment
Property, plant and equipment, gross										16,351,000	16,998,000
Other furniture and equipment
Property, plant and equipment
Property, plant and equipment, gross										952,000	841,000
Asset retirement cost
Property, plant and equipment
Property, plant and equipment, gross										992,000	1,285,000
Mineral Properties Asset Group
Property, plant and equipment
Impairment of long lived assets								$ 13,181,000
Mineral Properties Asset Group | Mineral and exploration properties
Property, plant and equipment
Property, plant and equipment, net								1,354,000	$ 1,354,000			$ 13,660,000
Impairment of long lived assets								12,306,000
Mineral Properties Asset Group | Mineral properties
Property, plant and equipment
Impairment of long lived assets								12,306,000
Mineral Properties Asset Group | Exploration properties
Property, plant and equipment
Property, plant and equipment, net												458,000
Impairment of long lived assets								458,000
Mineral Properties Asset Group | Asset retirement cost
Property, plant and equipment
Property, plant and equipment, net												417,000
Impairment of long lived assets								417,000
Velardena properties
Property, plant and equipment
Property, plant and equipment, gross								36,057,000	36,057,000			49,238,000
Velardena properties | Mineral and exploration properties
Property, plant and equipment
Impairment of long lived assets									12,800,000
Velardena properties | Mineral properties
Property, plant and equipment
Property, plant and equipment, gross								9,630,000	9,630,000			21,936,000
Velardena properties | Exploration properties
Property, plant and equipment
Property, plant and equipment, gross								2,543,000	2,543,000			3,001,000
Velardena properties | Royalty properties
Property, plant and equipment
Property, plant and equipment, gross								200,000	200,000			200,000
Velardena properties | Buildings
Property, plant and equipment
Property, plant and equipment, gross								4,377,000	4,377,000			4,377,000
Velardena properties | Mining equipment and machinery
Property, plant and equipment
Property, plant and equipment, gross								17,181,000	17,181,000			17,181,000
Velardena properties | Other furniture and equipment
Property, plant and equipment
Property, plant and equipment, gross								841,000	841,000			841,000
Velardena properties | Asset retirement cost
Property, plant and equipment
Property, plant and equipment, gross								$ 1,285,000	$ 1,285,000			$ 1,702,000
Peruvian exploration properties | Sale, not discontinued operations
Property, plant and equipment
Proceeds from sale of assets											$ 300,000
San Diego | Golden Tag
Property, plant and equipment
Net smelter return royalty (as a percent)		2.00%
San Diego | Golden Tag | Equipment sale
Property, plant and equipment
Net book value of disposals		$ 0
Gain on sale of equipment		500,000
San Diego | Golden Tag | Sale, not discontinued operations
Property, plant and equipment
Proceeds from sale of assets		$ 379,000
Ownership in property (as a percent)		50.00%
Shares received | shares		2,500,000
San Diego | Golden Tag
Property, plant and equipment
Ownership in property (as a percent)		50.00%
Celaya | Electrum
Property, plant and equipment
Gain on sale of equipment							$ 200,000
Ownership percentage							100.00%
Payments to acquire property							$ 200,000
Earn-in obligation							$ 500,000
Zacatecas Properties | Santa Cruz
Property, plant and equipment
Total consideration			$ 1,500,000
Gain on sale of equipment										$ 400,000
Proceeds from sale of assets			$ 200,000			$ 200,000
Due 12 months after signing agreement				$ 300,000
Due 18 months after signing agreement				300,000
Due 24 months after signing agreement				$ 500,000
Golden Tag
Property, plant and equipment
Ownership percentage										10.00%
Investment shares held (in shares) | shares										7,500,000
Minera Inde | Sale, not discontinued operations | Equipment sale
Property, plant and equipment
Number of haul trucks sold | item	2
Number of scoop trams sold | item	2
Total consideration	$ 687,000
Net book value of disposals	27,000
Gain on sale of equipment	660,000
Proceeds from sale of assets	$ 69,000
Sales price received (as a percent)	10.00%
Related party receivable	$ 618,000									$ 643,000
Interest rate on receivable (as a percent)	10.00%
Forecast | Minera Inde | Sale, not discontinued operations | Equipment sale
Property, plant and equipment
Net book value of disposals					$ 185,000
Proceeds from sale of assets					100,000
Related party receivable					$ 737,000
Interest rate on receivable (as a percent)					10.00%