Note 8 - Financial Highlights (Tables)

9 Months Ended

Sep. 30, 2015

Financial Highlights [Abstract]

Financial Highlights [Table Text Block]

	Three Months Ended						Nine Months Ended
	September 30,						September 30,
	2015			2014			2015			2014
Net asset value per Share, beginning of period	$	21.18		$	33.82		$	21.36		$	32.17
Net investment loss(a)		(0.04	)		(0.06	)		(0.12	)		(0.19	)
Net realized and unrealized loss(b)		(4.11	)		(4.22	)		(4.21	)		(2.44	)
Net decrease in net assets from operations		(4.15	)		(4.28	)		(4.33	)		(2.63	)
Net asset value per Share, end of period	$	17.03		$	29.54		$	17.03		$	29.54
Total return(c)(d)		(19.59	)%		(12.66	)%		(20.27	)%		(8.18	)%
Ratio to average net assets:
Net investment loss(e)		(0.82	)%		(0.77	)%		(0.81	)%		(0.77	)%
Expenses(e)		0.84	%		0.80	%		0.83	%		0.82	%