Schedule of Investments (Unaudited) - Treasury Bills and Affiliated Investments - USD ($) | 9 Months Ended | 12 Months Ended |
Sep. 30, 2017 | Dec. 31, 2016 |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | | 100.55% | | 100.01% | |
Value | | $ 122,708,590 | | $ 183,837,528 | |
Affiliated investments, at value | | 24,944,932 | | 9,388,271 | |
Total Investments in Securities | | 147,653,522 | | 193,225,799 | |
Investments, cost | | $ 147,552,410 | | 193,231,443 | |
Affiliated Investments [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | | 16.98% | | | |
Affiliated investments, at value | | $ 24,944,932 | | | |
Affiliated investments, at cost | | $ 24,854,663 | | $ 9,388,271 | |
U.S. Treasury Bills, 0.970% due October 26, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1] | 3.40% | | | |
Value | [1] | $ 4,996,896 | | | |
Principal Value | [1] | $ 5,000,000 | | | |
Investment Interest Rate | [1] | 0.97% | | | |
Investment Maturity Date | [1] | Oct. 26, 2017 | | | |
U.S. Treasury Bills, 1.000% due November 24, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1] | 28.56% | | | |
Value | [1] | $ 41,938,835 | | | |
Principal Value | [1] | $ 42,000,000 | | | |
Investment Interest Rate | [1] | 1.00% | | | |
Investment Maturity Date | [1] | Nov. 24, 2017 | | | |
U.S. Treasury Bills, 1.020% due December 7, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1] | 3.40% | | | |
Value | [1] | $ 4,991,017 | | | |
Principal Value | [1] | $ 5,000,000 | | | |
Investment Interest Rate | [1] | 1.02% | | | |
Investment Maturity Date | [1] | Dec. 7, 2017 | | | |
U.S. Treasury Bills, 1.050% due January 4, 2018 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1],[2] | 38.72% | | | |
Value | [1],[2] | $ 56,847,029 | | | |
Principal Value | [1],[2] | $ 57,000,000 | | | |
Investment Interest Rate | [1],[2] | 1.05% | | | |
Investment Maturity Date | [1],[2] | Jan. 4, 2018 | | | |
Restricted for maintenance margin | | $ 22,937,900 | | | |
U.S. Treasury Bills, 1.115% due March 1, 2018 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1] | 9.49% | | | |
Value | [1] | $ 13,934,813 | | | |
Principal Value | [1] | $ 14,000,000 | | | |
Investment Interest Rate | [1] | 1.115% | | | |
Investment Maturity Date | [1] | Mar. 1, 2018 | | | |
United States Treasury Obligations [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | | 83.57% | [1] | 95.15% | [3] |
Value | | $ 122,708,590 | [1] | $ 183,837,528 | [3] |
Investments, cost | | $ 122,697,747 | | $ 183,843,172 | |
Exchange Traded Funds [Member] | Affiliated Investments [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [4],[5] | 13.68% | | | |
Affiliated investments, at value | [4],[5] | $ 20,090,330 | | | |
Affiliated investments, shares | [4],[5] | 189,800 | | | |
Affiliated investments, at cost | [4],[5] | $ 20,000,061 | | | |
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 | | 3.30% | [6] | 4.86% | [7] |
Affiliated investments, at value | | $ 4,854,602 | [6] | $ 9,388,271 | [7] |
Affiliated investments, shares | | 4,854,602 | [6] | 9,388,271 | [7] |
Investment Interest Rate | | 0.92% | [6] | 0.41% | [7] |
Affiliated investments, at cost | | $ 4,854,602 | [6] | $ 9,388,271 | [7] |
U.S. Treasury Bills, 0.490% due January 19, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [3] | | | 9.83% | |
Value | [3] | | | $ 18,996,561 | |
Principal Value | [3] | | | $ 19,000,000 | |
Investment Interest Rate | [3] | | | 0.49% | |
Investment Maturity Date | [3] | | | Jan. 19, 2017 | |
U.S. Treasury Bills, 0.485% due January 26, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [3] | | | 25.35% | |
Value | [3] | | | $ 48,987,113 | |
Principal Value | [3] | | | $ 49,000,000 | |
Investment Interest Rate | [3] | | | 0.485% | |
Investment Maturity Date | [3] | | | Jan. 26, 2017 | |
U.S. Treasury Bills, 0.490% due March 2, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [3] | | | 27.41% | |
Value | [3] | | | $ 52,959,455 | |
Principal Value | [3] | | | $ 53,000,000 | |
Investment Interest Rate | [3] | | | 0.49% | |
Investment Maturity Date | [3] | | | Mar. 2, 2017 | |
U.S. Treasury Bills, 0.530% due April 6, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [3],[8] | | | 20.68% | |
Value | [3],[8] | | | $ 39,946,080 | |
Principal Value | [3],[8] | | | $ 40,000,000 | |
Investment Interest Rate | [3],[8] | | | 0.53% | |
Investment Maturity Date | [3],[8] | | | Apr. 6, 2017 | |
Restricted for maintenance margin | | | | $ 22,967,800 | |
U.S. Treasury Bills, 0.625% due May 18, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [3] | | | 11.88% | |
Value | [3] | | | $ 22,948,319 | |
Principal Value | [3] | | | $ 23,000,000 | |
Investment Interest Rate | [3] | | | 0.625% | |
Investment Maturity Date | [3] | | | May 18, 2017 | |
| |
[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 $22,937,900 are on deposit with the Commodity Broker and held as maintenance margin for open futures contracts. | |
[3] | 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 year end. | |
[4] | Affiliated company. The security and the Fund are affiliated by having the same investment adviser. See Note 8. | |
[5] | Non-Income producing security. | |
[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 September 30, 2017. | |
[7] | 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, 2016. | |
[8] | United States Treasury Obligations of $22,967,800 are on deposit with the Commodity Broker and held as maintenance margin for open futures contracts. | |