Creations and Redemptions (Details) - USD ($)	3 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
ETF MANAGERS GROUP COMMODITY TRUST I [Member]
Shares Sold, Shares	300,000	0
Shares Redeemed, Shares	(50,000)	(300,000)
Net Increase (Decrease), Shares	250,000	(300,000)
Shares Sold, Capital Increase (Decrease)	$ 6,825,745
Shares Redeemed, Capital Increase (Decrease)	(1,148,230)	(6,751,830)
Net Increase (Decrease), Capital Increase (Decrease)	$ 5,677,515	$ (6,751,830)
SIT RISING RATE ETF [Member]
Shares Sold, Shares	300,000	0
Shares Redeemed, Shares	(50,000)	(300,000)
Net Increase (Decrease), Shares	250,000	(300,000)
Shares Sold, Capital Increase (Decrease)	$ 6,825,745
Shares Redeemed, Capital Increase (Decrease)	(1,148,230)	(6,751,830)
Net Increase (Decrease), Capital Increase (Decrease)	$ 5,677,515	$ (6,751,830)