Note 15 - Acquisitions - Preliminary Purchase Price Allocation (Details) (Parentheticals) - Klondex Mines Ltd [Member]	Jul. 20, 2018 $ / shares shares
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares \| shares	75,276,176
Stock Issued, per share (in dollars per share) \| $ / shares	$ 3.22

Number of shares of equity interests issued or issuable to acquire entity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration