Joint Venture - Summary of Loans to Joint Venture (Parenthetical) (Details) - Minera Exar	9 Months Ended
Sep. 30, 2018
Granted in 2017
Disclosure Of Joint Ventures [Line Items]
Borrowings, interest rate basis	LIBOR+7.57%
Maturity period of borrowings	7 years
Granted in 2017 \| LIBOR
Disclosure Of Joint Ventures [Line Items]
Borrowings, adjustment to interest rate basis	7.57%
Granted in 2018
Disclosure Of Joint Ventures [Line Items]
Borrowings, interest rate basis	LIBOR+7.57%
Maturity period of borrowings	7 years
Granted in 2018 \| LIBOR
Disclosure Of Joint Ventures [Line Items]
Borrowings, adjustment to interest rate basis	7.57%

The adjustment to the basis (reference rate) used for calculation of the interest rate on borrowings. [Refer: Borrowings]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 7
-IssueDate 2017-01-01
-Paragraph 7
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_7&doctype=Standard
-URIDate 2017-03-09

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The basis (reference rate) used for calculation of the interest rate on borrowings. [Refer: Borrowings]

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The maturity of borrowings. [Refer: Borrowings]

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

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No definition available.

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