Note 14 - Income Taxes - Net Operating Losses (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)
Non-capital Income Tax Losses, Net [Member]
Tax credits	$ 32,002
Tax credits, expiration years	Jan. 01, 2026
Research Tax Credit Carryforward [Member]
Tax credits	$ 3,284
Tax Credits [Member]
Tax credits	$ 525
Tax credits, expiration years	Jan. 01, 2020

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant