XML 83 R56.htm IDEA: XBRL DOCUMENT
v3.21.1

Other Liabilities (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2020
Other Liabilities [abstract] |
Summary of other liabilities |
|  | December 31, |  | December 31,
|  | 2020 |  | 2019
Restricted share units (note 20(b)) |  | $ | 2,264 |  | $ | 246
Other non-current liabilities |  |  | 259 |  |  | 253
|  | $ | 2,523 |  | $ | 499

X
- Definition Disclosure of Other Liabilities [abstract]. + References No definition available. + Details
Name: | fsm_DisclosureOfOtherLiabilitiesAbstract
Namespace Prefix: | fsm_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of other liabilities. + References No definition available. + Details
Name: | fsm_DisclosureOfOtherLiabilitiesTextBlock
Namespace Prefix: | fsm_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration