Statement of Changes in Shareholders' Equity (Unaudited) - USD ($)	Total	General Shares [Member]	Shares [Member]
Balance - Value at Dec. 31, 2015	$ 17,518,991	$ 876	$ 17,518,115
Balance - Shares at Dec. 31, 2015		40	800,000
Net Income (Loss)
Net Investment Income (Loss)	(51,746)	$ (3)	$ (51,743)
Net Realized Gain (Loss) on United States Treasury Obligations, Affiliated Investments and Commodity Futures Contracts	773,895	39	773,856
Net Change in Unrealized Gain (Loss) on United States Treasury Obligations, Affiliated Investments and Commodity Futures Contracts	5,249,984	262	5,249,722
Net Income (Loss)	5,972,133	298	5,971,835
Net Change in Shareholders' Equity, value	5,972,133	298	5,971,835
Balance - Value at Jun. 30, 2016	23,491,124	$ 1,174	$ 23,489,950
Balance - Shares at Jun. 30, 2016		40	800,000
Balance - Value at Mar. 31, 2016	19,605,131	$ 980	$ 19,604,151
Balance - Shares at Mar. 31, 2016		40	800,000
Net Income (Loss)
Net Investment Income (Loss)	(25,822)	$ (2)	$ (25,820)
Net Realized Gain (Loss) on United States Treasury Obligations, Affiliated Investments and Commodity Futures Contracts	3,923	1	3,922
Net Change in Unrealized Gain (Loss) on United States Treasury Obligations, Affiliated Investments and Commodity Futures Contracts	3,907,892	195	3,907,697
Net Income (Loss)	3,885,993	194	3,885,799
Net Change in Shareholders' Equity, value	3,885,993	194	3,885,799
Balance - Value at Jun. 30, 2016	23,491,124	$ 1,174	$ 23,489,950
Balance - Shares at Jun. 30, 2016		40	800,000
Balance - Value at Dec. 31, 2016	24,945,521	$ 998	$ 24,944,523
Balance - Shares at Dec. 31, 2016		40	1,000,000
Purchases of Shares - Value	5,755,806		$ 5,755,806
Purchases of Shares - Shares			200,000
Redemption of Shares - Value	(10,696,877)		$ (10,696,877)
Redemption of Shares - Shares			(400,000)
Net Increase (Decrease) due to Share Transactions, value	(4,941,071)		$ (4,941,071)
Net Increase (Decrease) due to Share Transactions, shares			(200,000)
Net Income (Loss)
Net Investment Income (Loss)	(14,232)	$ (1)	$ (14,231)
Net Realized Gain (Loss) on United States Treasury Obligations, Affiliated Investments and Commodity Futures Contracts	739,888	38	739,850
Net Change in Unrealized Gain (Loss) on United States Treasury Obligations, Affiliated Investments and Commodity Futures Contracts	(199,065)	(9)	(199,056)
Net Income (Loss)	526,591	28	526,563
Net Change in Shareholders' Equity, value	(4,414,480)	28	$ (4,414,508)
Net Change in Shareholders' Equity, shares			(200,000)
Balance - Value at Jun. 30, 2017	20,531,041	$ 1,026	$ 20,530,015
Balance - Shares at Jun. 30, 2017		40	800,000
Balance - Value at Mar. 31, 2017	28,381,873	$ 1,135	$ 28,380,738
Balance - Shares at Mar. 31, 2017		40	1,000,000
Purchases of Shares - Value	5,755,806		$ 5,755,806
Purchases of Shares - Shares			200,000
Redemption of Shares - Value	(10,696,877)		$ (10,696,877)
Redemption of Shares - Shares			(400,000)
Net Increase (Decrease) due to Share Transactions, value	(4,941,071)		$ (4,941,071)
Net Increase (Decrease) due to Share Transactions, shares			(200,000)
Net Income (Loss)
Net Investment Income (Loss)	(1,013)		$ (1,013)
Net Realized Gain (Loss) on United States Treasury Obligations, Affiliated Investments and Commodity Futures Contracts	(197,978)		(197,978)
Net Change in Unrealized Gain (Loss) on United States Treasury Obligations, Affiliated Investments and Commodity Futures Contracts	(2,710,770)	$ (109)	(2,710,661)
Net Income (Loss)	(2,909,761)	(109)	(2,909,652)
Net Change in Shareholders' Equity, value	(7,850,832)	(109)	$ (7,850,723)
Net Change in Shareholders' Equity, shares			(200,000)
Balance - Value at Jun. 30, 2017	$ 20,531,041	$ 1,026	$ 20,530,015
Balance - Shares at Jun. 30, 2017		40	800,000