Equity securities, FV-NI cost short term investments.

No definition available.

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Namespace Prefix:	aumn_
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Period Type:	instant

- Definition

Represents the ownership percentage in a property or project.

+ References

No definition available.

+ Details

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Balance Type:	na
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- References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

+ Details

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Period Type:	instant

- Definition

Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=116654751&loc=SL75117546-209714

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Balance held at close of period in number of shares.

+ References

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Balance Type:	na
Period Type:	instant

- Definition

The lowest amount of net worth (total assets minus total liabilities) required by secondary market investors or state-imposed regulatory mandates.

+ References

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- Definition

The net cash paid (received) associated with the acquisition or disposal of all investments, including securities and other assets.

+ References

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- Definition

Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

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- Details

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- Details

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- Details

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Cash and Cash Equivalents and Short-term Investments (Details) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2017
Investments:
Trading securities, cost			$ 275,000
Total short term, cost			275,000
Trading securities						$ 238,000
Total short term			$ 330,000
Financial institutions minimum net worth		$ 1,000,000,000
Golden Tag
Investments:
Investment shares held (in shares)		0	7,500,000
Ownership in property (as a percent)			10.00%
Net proceeds from the sale of shares	$ 113,000
Loss on sale of shares		$ 217,000
Trading securities
Investments:
Trading securities, cost			$ 275,000
Estimated Fair Value.
Investments:
Trading securities			330,000
Total short term			330,000
Estimated Fair Value. \| Trading securities
Investments:
Trading securities			330,000
Carrying Value.
Investments:
Trading securities			330,000
Total short term			330,000
Carrying Value. \| Trading securities
Investments:
Trading securities			$ 330,000
San Diego \| Golden Tag
Investments:
Ownership in property (as a percent)				50.00%	50.00%