Statement of Changes in Shareholders' Equity (Unaudited) - USD ($)	Total	Shares [Member]	General Shares [Member]
Balance - Value at Dec. 31, 2018	$ 1,932,576,856	$ 1,932,576,278	$ 578
Balance - Shares at Dec. 31, 2018		133,800,000	40
Purchases of Shares - Value	51,179,193	$ 51,179,193
Purchases of Shares - Shares		3,400,000
Redemption of Shares - Value	(677,971,167)	$ (677,971,167)
Redemption of Shares - Shares		(43,600,000)
Net Increase (Decrease) due to Share Transactions, value	(626,791,974)	$ (626,791,974)
Net Increase (Decrease) due to Share Transactions, shares		(40,200,000)
Net Income (Loss)
Net Investment Income (Loss)	18,890,547	$ 18,890,542	$ 5
Net Realized Gain (Loss) on United States Treasury Obligations, Affiliated Investments and Commodity Futures Contracts	(101,973,925)	(101,973,902)	(23)
Net Change in Unrealized Gain (Loss) on United States Treasury Obligations, Affiliated Investments and Commodity Futures Contracts	182,657,599	182,657,559	40
Net Income (Loss)	99,574,221	99,574,199	22
Net Change in Shareholders' Equity, value	(527,217,753)	$ (527,217,775)	22
Net Change in Shareholders' Equity, shares		(40,200,000)
Balance - Value at Sep. 30, 2019	1,405,359,103	$ 1,405,358,503	$ 600
Balance - Shares at Sep. 30, 2019		93,600,000	40
Balance - Value at Jun. 30, 2019	1,608,783,674	$ 1,608,783,043	$ 631
Balance - Shares at Jun. 30, 2019		102,000,000	40
Purchases of Shares - Value	3,000,952	$ 3,000,952
Purchases of Shares - Shares		200,000
Redemption of Shares - Value	(130,451,567)	$ (130,451,567)
Redemption of Shares - Shares		(8,600,000)
Net Increase (Decrease) due to Share Transactions, value	(127,450,615)	$ (127,450,615)
Net Increase (Decrease) due to Share Transactions, shares		(8,400,000)
Net Income (Loss)
Net Investment Income (Loss)	5,261,389	$ 5,261,388	$ 1
Net Realized Gain (Loss) on United States Treasury Obligations, Affiliated Investments and Commodity Futures Contracts	(40,870,611)	(40,870,606)	(5)
Net Change in Unrealized Gain (Loss) on United States Treasury Obligations, Affiliated Investments and Commodity Futures Contracts	(40,364,734)	(40,364,707)	(27)
Net Income (Loss)	(75,973,956)	(75,973,925)	(31)
Net Change in Shareholders' Equity, value	(203,424,571)	$ (203,424,540)	(31)
Net Change in Shareholders' Equity, shares		(8,400,000)
Balance - Value at Sep. 30, 2019	1,405,359,103	$ 1,405,358,503	$ 600
Balance - Shares at Sep. 30, 2019		93,600,000	40
Balance - Value at Dec. 31, 2019	1,428,657,083	$ 1,428,656,445	$ 638
Balance - Shares at Dec. 31, 2019		89,600,000	40
Purchases of Shares - Value	255,230,466	$ 255,230,466
Purchases of Shares - Shares		19,400,000
Redemption of Shares - Value	(375,246,076)	$ (375,246,076)
Redemption of Shares - Shares		(28,600,000)
Net Increase (Decrease) due to Share Transactions, value	(120,015,610)	$ (120,015,610)
Net Increase (Decrease) due to Share Transactions, shares		(9,200,000)
Net Income (Loss)
Net Investment Income (Loss)	(58,810)	$ (58,810)	$ 0
Net Realized Gain (Loss) on United States Treasury Obligations, Affiliated Investments and Commodity Futures Contracts	(209,222,504)	(209,222,411)	(93)
Net Change in Unrealized Gain (Loss) on United States Treasury Obligations, Affiliated Investments and Commodity Futures Contracts	(47,252,900)	(47,252,879)	(21)
Net Income (Loss)	(256,534,214)	(256,534,100)	(114)
Net Change in Shareholders' Equity, value	(376,549,824)	$ (376,549,710)	(114)
Net Change in Shareholders' Equity, shares		(9,200,000)
Balance - Value at Sep. 30, 2020	1,052,107,259	$ 1,052,106,735	$ 524
Balance - Shares at Sep. 30, 2020		80,400,000	40
Balance - Value at Jun. 30, 2020	851,267,605	$ 851,267,113	$ 492
Balance - Shares at Jun. 30, 2020		69,200,000	40
Purchases of Shares - Value	173,286,373	$ 173,286,373
Purchases of Shares - Shares		13,200,000
Redemption of Shares - Value	(26,216,258)	$ (26,216,258)
Redemption of Shares - Shares		(2,000,000)
Net Increase (Decrease) due to Share Transactions, value	147,070,115	$ 147,070,115
Net Increase (Decrease) due to Share Transactions, shares		11,200,000
Net Income (Loss)
Net Investment Income (Loss)	(1,728,048)	$ (1,728,047)	$ (1)
Net Realized Gain (Loss) on United States Treasury Obligations, Affiliated Investments and Commodity Futures Contracts	(18,218,227)	(18,218,224)	(3)
Net Change in Unrealized Gain (Loss) on United States Treasury Obligations, Affiliated Investments and Commodity Futures Contracts	73,715,814	73,715,778	36
Net Income (Loss)	53,769,539	53,769,507	32
Net Change in Shareholders' Equity, value	200,839,654	$ 200,839,622	32
Net Change in Shareholders' Equity, shares		11,200,000
Balance - Value at Sep. 30, 2020	$ 1,052,107,259	$ 1,052,106,735	$ 524
Balance - Shares at Sep. 30, 2020		80,400,000	40