Represents the additional ownership percentage in Joint Venture.

No definition available.

Name:	aumn_AdditionalOwnershipPercentageInJointVenture
Namespace Prefix:	aumn_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of expenditure incurred during the second three year period of the agreement.

+ References

No definition available.

+ Details

Name:	aumn_AdditionalPaymentInJointVentureDuringSecondThreeYearPeriodOfAgreement
Namespace Prefix:	aumn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage of ownership in a joint venture.

+ References

No definition available.

+ Details

Name:	aumn_OwnershipPercentageInJointVenture
Namespace Prefix:	aumn_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the percentage of contribution from additional expenditures required in the second three-year earn-in period

+ References

No definition available.

+ Details

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

- Definition

The term of the second agreement.

+ References

No definition available.

+ Details

Name:	aumn_TermOfSecondAgreement
Namespace Prefix:	aumn_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64827811&loc=d3e1361-107760

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84176398&loc=d3e2941-110230

+ Details

Name:	us-gaap_GainLossOnDispositionOfAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

+ Details

Name:	us-gaap_PaymentsToAcquireInterestInJointVenture
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

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

- Details

Name:	us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=aumn_CelayaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=aumn_ElectrumGlobalHoldingsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Subsequent Event (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
Subsequent Event (Details) - USD ($) $ in Thousands	Feb. 28, 2018	Aug. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Subsequent Events
Gain on sale of assets			$ 608	$ 1,791
Celaya
Subsequent Events
Exploration expenditures in second three year of the agreement		$ 2,500
Term of second agreement		3 years
Gain on sale of assets				$ 200
Subsequent Event \| Celaya
Subsequent Events
Additional interest in joint venture (as a percent)	20.00%
Payment to acquire additional interest in joint venture	$ 1,000
Contribution from additional expenditures required in the second three-year earn-in period (as a percent)	100.00%
Exploration expenditures in second three year of the agreement	$ 2,500
Gain on sale of assets	$ 1,000
Subsequent Event \| Celaya \| Maximum
Subsequent Events
Interest in joint venture (as a percent)	80.00%
Electrum \| Celaya
Subsequent Events
Investment ownership percentage		100.00%
Interest in joint venture (as a percent)		60.00%