Schedule of Investments (Unaudited) - Treasury Bills and Money Market Fund - USD ($)		Mar. 31, 2020		Dec. 31, 2019
Schedule Of Investments [Line Items]
Percentage of Shareholders' Equity		116.71%		97.21%
United States Treasury Obligations, Value		$ 76,994,177		$ 55,798,273
Affiliated investments, Value		21,406,990		57,894,114
Investments in Securities, Value		98,401,167		113,692,387
Investments in Securities, cost		$ 98,254,396		$ 113,645,878
Affiliated Investments [Member]
Schedule Of Investments [Line Items]
Percentage of Shareholders' Equity		25.39%		49.50%
Affiliated investments, Value		$ 21,406,990		$ 57,894,114
Affiliated Investments, Cost		$ 21,283,100		$ 57,868,959
U.S. Treasury Bills, 1.520% due April 2, 2020 [Member]
Schedule Of Investments [Line Items]
Percentage of Shareholders' Equity	[1]	53.37%	[2]	38.33%	[3]
United States Treasury Obligations, Value	[1]	$ 45,000,012	[2]	$ 44,827,100	[3]
United States Treasury Obligations, Principal Value	[1]	$ 45,000,000	[2]	$ 45,000,000	[3]
Investment Interest Rate	[1]	1.52%	[2]	1.52%	[3]
Investment Maturity Date	[1]	Apr. 02, 2020	[2]	Apr. 02, 2020	[3]
Restricted for maintenance margin		$ 51,992,800		$ 10,957,100
U.S. Treasury Bills, 1.505% due May 28, 2020 [Member]
Schedule Of Investments [Line Items]
Percentage of Shareholders' Equity	[1],[2]	14.23%
United States Treasury Obligations, Value	[1],[2]	$ 11,998,765
United States Treasury Obligations, Principal Value	[1],[2]	$ 12,000,000
Investment Interest Rate	[1],[2]	1.505%
Investment Maturity Date	[1],[2]	May 28, 2020
Restricted for maintenance margin		$ 51,992,800
U.S. Treasury Bills, 0.085% due July 2, 2020 [Member]
Schedule Of Investments [Line Items]
Percentage of Shareholders' Equity	[1],[2]	23.72%
United States Treasury Obligations, Value	[1],[2]	$ 19,995,400
United States Treasury Obligations, Principal Value	[1],[2]	$ 20,000,000
Investment Interest Rate	[1],[2]	0.085%
Investment Maturity Date	[1],[2]	Jul. 02, 2020
Restricted for maintenance margin		$ 51,992,800
United States Treasury Obligations [Member]
Schedule Of Investments [Line Items]
Percentage of Shareholders' Equity	[1]	91.32%		47.71%
United States Treasury Obligations, Value	[1]	$ 76,994,177		$ 55,798,273
Investments in Securities, cost	[1]	$ 76,971,296		$ 55,776,919
Exchange-Traded Fund [Member] | Affiliated Investments [Member]
Schedule Of Investments [Line Items]
Percentage of Shareholders' Equity	[4]	19.13%		13.71%
Affiliated investments, Value	[4]	$ 16,130,261		$ 16,031,526
Affiliated Investments, Shares	[4]	151,900		151,900
Affiliated Investments, Cost	[4]	$ 16,006,371		$ 16,006,371
Money Market Mutual Fund - Premier U.S. Government Money Portfolio - Institutional Class [Member] | Affiliated Investments [Member]
Schedule Of Investments [Line Items]
Percentage of Shareholders' Equity		6.26%	[5]	35.79%	[6]
Affiliated investments, Value		$ 5,276,729	[5]	$ 41,862,588	[6]
Affiliated Investments, Shares		5,276,729	[5]	41,862,588	[6]
Investment Interest Rate		0.54%	[5]	1.47%	[6]
Affiliated Investments, Cost		$ 5,276,729	[5]	$ 41,862,588	[6]
U.S. Treasury Bills, 1.560% due March 5, 2020 [Member]
Schedule Of Investments [Line Items]
Percentage of Shareholders' Equity	[1]			9.38%
United States Treasury Obligations, Value	[1]			$ 10,971,173
United States Treasury Obligations, Principal Value	[1]			$ 11,000,000
Investment Interest Rate	[1]			1.56%
Investment Maturity Date	[1]			Mar. 05, 2020
Restricted for maintenance margin				$ 10,957,100

[1] Security may be traded on a discount basis. The interest rate shown represents the discount rate at the most recent auction date of the security prior to period end.

[2] United States Treasury Obligations of $51,992,800 are on deposit with the Commodity Broker and held as maintenance margin for open futures contracts.

[3] United States Treasury Obligations of $10,957,100 are on deposit with the Commodity Broker and held as maintenance margin for open futures contracts.

[4] Affiliated company. The security and the Fund are affiliated by having the same investment adviser. See Note 8.

[5] The security and the Fund are advised by wholly-owned subsidiaries of Invesco Ltd. and are therefore considered to be affiliated. The rate shown is the 7-day SEC standardized yield as of March 31, 2020.

[6] The security and the Fund are advised by wholly-owned subsidiaries of Invesco Ltd. and are therefore considered to be affiliated. The rate shown is the 7-day SEC standardized yield as of December 31, 2019.