Nature of Operations - Additional Information (Details)	9 Months Ended
Sep. 30, 2018 Project
Nature Of Operations [Abstract]
Name of reporting entity	Lithium Americas Corp.
Number of significant projects	2

The name of the reporting entity or other means of identification.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 51
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_51_a&doctype=Standard
-URIDate 2017-03-09

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