The number of shares received for consideration.

No definition available.

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- Definition

The amount of first year anniversary consideration

+ References

No definition available.

+ Details

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Namespace Prefix:	aumn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The number of Business Days to Conduct Due Diligence.

+ References

No definition available.

+ Details

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Namespace Prefix:	aumn_
Data Type:	xbrli:durationItemType
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- Definition

The percentage of interest claims.

+ References

No definition available.

+ Details

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Namespace Prefix:	aumn_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of net royalty return.

+ References

No definition available.

+ Details

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Namespace Prefix:	aumn_
Data Type:	num:percentItemType
Balance Type:	na
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- Definition

The percentage of underwriting discount.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

The amount of second year anniversary consideration

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The amount of secure financing able to provide.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Reduction in cash due to no longer including the former subsidiary's cash in the consolidated entity's cash.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Nonrecurring impairment charges related to the write-off of production-related equipment and inventory. This tag is used when an Entity charges this cost to cost of goods sold.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(a))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=aumn_FirmCommitmentOfferingMember
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- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
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- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Namespace Prefix:
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- Details

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Subsequent Events (Details) $ / shares in Units, $ in Thousands					6 Months Ended
	Jul. 21, 2020 USD ($) $ / shares shares	Jul. 14, 2020 CAD ($) shares	Jul. 14, 2020 USD ($) shares	Apr. 20, 2020 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)
Subsequent Event
Impairment charges					$ 0
Proceeds from Issuance of Common Stock					$ 4,079,000	$ 544,000
Private Placement
Subsequent Event
Total cost of offering				$ 334,000
Firm Commitment Offering \| Subsequent Event
Subsequent Event
Number of shares to purchase in agreement \| shares	17,857,143
Purchase price \| $ / shares	$ 0.42
Percentage of underwriting discount	6.00%
Total cost of offering	$ 225,000
Proceeds from Issuance of Common Stock	$ 7,900,000
Over-Allotment Option \| Subsequent Event
Subsequent Event
Number of shares to purchase in agreement \| shares	2,678,571
Binding Letter of Intent Agreement \| Fabled Copper Corp. \| Sale of Santa Maria Property \| Subsequent Event
Subsequent Event
Percentage of interest claims		100.00%	100.00%
Number of Business Days to Conduct Due Diligence		10 days	10 days
Secure financing amount		$ 4,000
Cash consideration received			$ 500,000
Consideration Received in Shares \| shares		1,000,000	1,000,000
First year anniversary consideration			$ 1,500,000
Second year anniversary consideration			$ 2,000,000
Percentage of royalty return		1.00%	1.00%