Note 4 - Accounts Receivable - Components of Accounts Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Statement Line Items [Line Items]
Goods and services tax ("GST") recoverable	$ 22	$ 23
Mexican value added tax ("IVA") recoverable	133	30
Interest receivable	217	107
	$ 372	$ 160

The amount of current interest receivable. [Refer: Interest receivable]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
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-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_112_c&doctype=Standard
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Balance Type:	debit
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- Definition

The amount of current receivables from taxes other than income tax. [Refer: Receivables from taxes other than income tax]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
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Period Type:	instant

- Definition

The amount of current trade receivables. [Refer: Trade receivables]

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
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Balance Type:	debit
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- Definition

The amount of current value added tax receivables. [Refer: Value added tax receivables]

+ References

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Data Type:	xbrli:monetaryItemType
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- References

No definition available.

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