Note 8 - Financial Highlights (Tables)

6 Months Ended

Jun. 30, 2015

Financial Highlights [Abstract]

Financial Highlights [Table Text Block]

	Three Months Ended June 30,						Six Months Ended June 30,
	2015			2014			2015			2014
Net asset value per Share, beginning of period	$	11.48		$	12.52		$	11.61		$	11.66
Net investment loss(a)		(0.01	)		(0.01	)		(0.01	)		(0.02	)
Net realized and unrealized gain (loss)(b)		(0.15	)		0.23			(0.28	)		1.10
Net increase (decrease) in net assets from operations		(0.16	)		0.22			(0.29	)		1.08
Net asset value per Share, end of period	$	11.32		$	12.74		$	11.32		$	12.74
Total return(c)(d)		(1.39	)%		1.76	%		(2.50	)%		9.26	%
Ratio to average net assets:
Net investment loss(e)		(0.25	)%		(0.25	)%		(0.25	)%		(0.25	)%
Expenses(e)		0.25	%		0.25	%		0.25	%		0.25	%