Note 4 - Related Parties	12 Months Ended
Dec. 31, 2017
Notes to Financial Statements
Related Party Transactions Disclosure [Text Block]	4 - Related Parties The Sponsor and the Trus tee are considered to be related parties to the Trust. The Trustee’s fee is paid by the Sponsor and is not a separate expense of the Trust.

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-URI http://asc.fasb.org/topic&trid=2122745

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