Promissory note (Details) - USD ($) $ in Millions	Dec. 15, 2020	Dec. 31, 2020
Promissory Note [Member]
Disclosure of detailed information about borrowings [line items]
Issue of promissory note		$ 0.1
Sandstorm Gold Ltd [Member]
Disclosure of detailed information about borrowings [line items]
Issue of promissory note	$ 0.5
Maturity date of promissory note	June 15, 2022
Interest rate on promissory note	7.00%

The interest rate on borrowings. [Refer: Borrowings]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The maturity of borrowings. [Refer: Borrowings]

+ References

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

+ References

No definition available.

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- Definition

The amount of non-current debt instruments issued. [Refer: Debt instruments issued]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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