(LOSS)/INCOME PER COMMON SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Earnings per share [abstract]
Net loss attributable to Golden Star shareholders	$ (67,434)	$ (18,123)
Weighted average shares outstanding-basic (in shares)	109.0	84.3
Loss per share attributable to Golden Star shareholders:
Basic (usd per share)	$ (0.62)	$ (0.21)
Diluted (usd per share)	$ (0.62)	$ (0.21)

No definition available.

Name:	ifrs-full_BasicAndDilutedEarningsPerShareAbstract
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator) divided by the weighted average number of ordinary shares outstanding during the period (the denominator).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 33
-IssueDate 2019-01-01
-Paragraph 66
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2019-en-r&anchor=para_66&doctype=Standard
-URIDate 2019-03-27

+ Details

Name:	ifrs-full_BasicEarningsLossPerShare
Namespace Prefix:	ifrs-full_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator), divided by the weighted average number of ordinary shares outstanding during the period (the denominator), both adjusted for the effects of all dilutive potential ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]]

+ References

+ Details

Name:	ifrs-full_DilutedEarningsLossPerShare
Namespace Prefix:	ifrs-full_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	ifrs-full_EarningsPerShareAbstract
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The profit (loss) attributable to ordinary equity holders of the parent entity. [Refer: Profit (loss)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 33
-IssueDate 2019-01-01
-Paragraph 70
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2019-en-r&anchor=para_70_a&doctype=Standard
-URIDate 2019-03-27

+ Details

Name:	ifrs-full_ProfitLossAttributableToOrdinaryEquityHoldersOfParentEntity
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The number of ordinary shares outstanding at the beginning of the period, adjusted by the number of ordinary shares bought back or issued during the period multiplied by a time-weighting factor.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 33
-IssueDate 2019-01-01
-Paragraph 70
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2019-en-r&anchor=para_70_b&doctype=Standard
-URIDate 2019-03-27

+ Details

Name:	ifrs-full_WeightedAverageShares
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration