Schedule of Investments - Treasury Bills and Affiliated Investments - USD ($) | 12 Months Ended |
Dec. 31, 2018 | Dec. 31, 2017 |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | | 99.86% | | 98.81% | |
United States Treasury Obligations, Value | | $ 227,905,176 | | $ 311,472,491 | |
Affiliated Investments, Value | | 33,302,539 | | 17,412,477 | |
Investments in Securities, Value | | 261,207,715 | | 328,884,968 | |
Investments in Securities, Cost | | $ 261,202,445 | | $ 328,926,740 | |
Affiliated Investments [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | | 12.73% | | 5.23% | |
Affiliated Investments, Value | | $ 33,302,539 | | $ 17,412,477 | |
Affiliated Investments, at Cost | | $ 33,299,423 | | $ 17,417,436 | |
U.S. Treasury Bills, 2.175% due January 3, 2019 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1] | 19.88% | | | |
United States Treasury Obligations, Value | [1] | $ 51,996,757 | | | |
United States Treasury Obligations, Principal Value | [1] | $ 52,000,000 | | | |
Investment Interest Rate | [1] | 2.175% | | | |
Investment Maturity Date | [1] | Jan. 3, 2019 | | | |
U.S. Treasury Bills, 2.370% due February 28, 2019 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1] | 12.95% | | | |
United States Treasury Obligations, Value | [1] | $ 33,872,079 | | | |
United States Treasury Obligations, Principal Value | [1] | $ 34,000,000 | | | |
Investment Interest Rate | [1] | 2.37% | | | |
Investment Maturity Date | [1] | Feb. 28, 2019 | | | |
U.S. Treasury Bills, 2.465% due April 4, 2019 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1],[2] | 37.99% | | | |
United States Treasury Obligations, Value | [1],[2] | $ 99,381,236 | | | |
United States Treasury Obligations, Principal Value | [1],[2] | $ 100,000,000 | | | |
Investment Interest Rate | [1],[2] | 2.465% | | | |
Investment Maturity Date | [1],[2] | Apr. 4, 2019 | | | |
U.S. Treasury Bills, 2.430% due May 2, 2019 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1],[2] | 16.31% | | | |
United States Treasury Obligations, Value | [1],[2] | $ 42,655,104 | | | |
United States Treasury Obligations, Principal Value | [1],[2] | $ 43,000,000 | | | |
Investment Interest Rate | [1],[2] | 2.43% | | | |
Investment Maturity Date | [1],[2] | May 2, 2019 | | | |
Restricted for maintenance margin | | $ 44,349,600 | | | |
United States Treasury Obligations [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1] | 87.13% | | 93.58% | |
United States Treasury Obligations, Value | [1] | $ 227,905,176 | | $ 311,472,491 | |
Investments in Securities, Cost | [1] | $ 227,903,022 | | $ 311,509,304 | [3] |
Exchange-Traded Fund [Member] | Affiliated Investments [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [4] | 1.91% | | 1.50% | |
Affiliated Investments, Value | [4] | $ 5,008,400 | | $ 5,000,325 | |
Affiliated Investments, Shares | [4] | 47,500 | | 47,500 | |
Affiliated Investments, at Cost | | $ 5,005,284 | [4] | $ 5,005,284 | |
Money Market Mutual Fund - Invesco Premier U.S. Government Money Portfolio - Institutional Class [Member] | Affiliated Investments [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | | 10.82% | [5] | 3.73% | [6] |
Affiliated Investments, Value | | $ 28,294,139 | [5] | $ 12,412,152 | [6] |
Affiliated Investments, Shares | | 28,294,139 | [5] | 12,412,152 | [6] |
Investment Interest Rate | | 2.30% | [5] | 1.15% | [4] |
Affiliated Investments, at Cost | | $ 28,294,139 | [5] | $ 12,412,152 | [4] |
U.S. Treasury Bills, 1.180% due January 4, 2018 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1] | | | 15.92% | |
United States Treasury Obligations, Value | [1] | | | $ 52,996,676 | |
United States Treasury Obligations, Principal Value | [1] | | | $ 53,000,000 | |
Investment Interest Rate | [1] | | | 1.18% | |
Investment Maturity Date | [1] | | | Jan. 4, 2018 | |
U.S. Treasury Bills, 1.245% due January 18, 2018 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1] | | | 2.70% | |
United States Treasury Obligations, Value | [1] | | | $ 8,995,065 | |
United States Treasury Obligations, Principal Value | [1] | | | $ 9,000,000 | |
Investment Interest Rate | [1] | | | 1.245% | |
Investment Maturity Date | [1] | | | Jan. 18, 2018 | |
U.S. Treasury Bills, 1.285% due February 22, 2018 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1] | | | 24.89% | |
United States Treasury Obligations, Value | [1] | | | $ 82,851,845 | |
United States Treasury Obligations, Principal Value | [1] | | | $ 83,000,000 | |
Investment Interest Rate | [1] | | | 1.285% | |
Investment Maturity Date | [1] | | | Feb. 22, 2018 | |
U.S. Treasury Bills, 1.450% due June 7, 2018 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1] | | | 2.09% | |
United States Treasury Obligations, Value | [1] | | | $ 6,955,638 | |
United States Treasury Obligations, Principal Value | [1] | | | $ 7,000,000 | |
Investment Interest Rate | [1] | | | 1.45% | |
Investment Maturity Date | [1] | | | Jun. 7, 2018 | |
U.S. Treasury Bills, 1.285% due March 1, 2018 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1],[3] | | | 47.98% | |
United States Treasury Obligations, Value | [1],[3] | | | $ 159,673,267 | |
United States Treasury Obligations, Principal Value | [1],[3] | | | $ 160,000,000 | |
Investment Interest Rate | [1] | | | 1.285% | |
Investment Maturity Date | [1] | | | Mar. 1, 2018 | |
Restricted for maintenance margin | | | | $ 39,916,000 | |
| |
[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 $44,349,600 are on deposit with the Commodity Broker and held as maintenance margin for open futures contracts. | |
[3] | United States Treasury Obligations of $39,916,000 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 December 31, 2018. | |
[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, 2017. | |