Consolidated Statements of Changes in Equity (Parenthetical) - $ / shares	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Statement of changes in equity [abstract]
Dividends payments to Methanex Corporation shareholders (in usd per share)	$ 1.320	$ 1.175

The amount, per share, of dividends recognised as distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 107
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_107&doctype=Standard
-URIDate 2017-03-09

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