Schedule of Investments (Unaudited) - Treasury Bills and Affiliated Investments - USD ($) | 6 Months Ended | 12 Months Ended |
Jun. 30, 2017 | Dec. 31, 2016 |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | | 97.47% | | 100.17% | |
Value | | $ 336,555,796 | | $ 438,601,879 | |
Affiliated Investments, at Value | | 54,092,207 | | 14,942,839 | |
Total Investments | | 390,648,003 | | 453,544,718 | |
Investments, cost | | $ 390,606,486 | | 453,552,275 | |
Affiliated Investments [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | | 13.49% | | | |
Affiliated Investments, at Value | | $ 54,092,207 | | | |
Affiliated Investments, at Cost | | $ 54,081,491 | | $ 14,942,839 | |
U.S. Treasury Bills, 0.840% due July 6, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1] | 2.50% | | | |
Value | [1] | $ 9,999,370 | | | |
Principal Value | [1] | $ 10,000,000 | | | |
Investment Interest Rate | [2] | 0.84% | | | |
Investment Maturity Date | [2] | Jul. 6, 2017 | | | |
U.S. Treasury Bills, 0.890% due July 27, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1],[3] | 19.45% | | | |
Value | [1],[3] | $ 77,957,646 | | | |
Principal Value | [1],[3] | $ 78,000,000 | | | |
Investment Interest Rate | [2],[3] | 0.89% | | | |
Investment Maturity Date | [2],[3] | Jul. 27, 2017 | | | |
Restricted for maintenance margin | | $ 59,964,000 | | | |
U.S. Treasury Bills, 0.905% due August 17, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1] | 6.48% | | | |
Value | [1] | $ 25,970,802 | | | |
Principal Value | [1] | $ 26,000,000 | | | |
Investment Interest Rate | [2] | 0.905% | | | |
Investment Maturity Date | [2] | Aug. 17, 2017 | | | |
U.S. Treasury Bills, 0.960% due August 31, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1] | 33.14% | | | |
Value | [1] | $ 132,799,968 | | | |
Principal Value | [1] | $ 133,000,000 | | | |
Investment Interest Rate | [2] | 0.96% | | | |
Investment Maturity Date | [2] | Aug. 31, 2017 | | | |
United States Treasury Obligations [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | | 83.98% | [1] | 96.87% | [2] |
Value | | $ 336,555,796 | [1] | $ 438,601,879 | [2] |
Investments, cost | | $ 336,524,995 | [1] | $ 438,609,436 | [2] |
U.S. Treasury Bills, 0.990% due September 14, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [1] | 22.41% | | | |
Value | [1] | $ 89,828,010 | | | |
Principal Value | [1] | $ 90,000,000 | | | |
Investment Interest Rate | [1] | 0.99% | | | |
Investment Maturity Date | [1] | Sep. 14, 2017 | | | |
Exchange-Traded Fund - PowerShares Treasury Collateral Portfolio [Member] | Affiliated Investments [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [4],[5] | 1.25% | | | |
Affiliated Investments, at Value | [4],[5] | $ 5,016,000 | | | |
Affiliated Investments, Shares | [4],[5] | 47,500 | | | |
Affiliated Investments, at Cost | [4],[5] | $ 5,005,284 | | | |
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 | | 12.24% | [6] | 3.30% | [7] |
Affiliated Investments, at Value | | $ 49,076,207 | [6] | $ 14,942,839 | [7] |
Affiliated Investments, Shares | | 49,076,207 | [6] | 14,942,839 | [7] |
Investment Interest Rate | | 0.86% | [6] | 0.41% | [7] |
Affiliated Investments, at Cost | | $ 49,076,207 | [6] | $ 14,942,839 | [7] |
U.S. Treasury Bills, 0.490% due January 19, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [2] | | | 9.50% | |
Value | [2] | | | $ 42,992,217 | |
Principal Value | [2] | | | $ 43,000,000 | |
Investment Interest Rate | [2] | | | 0.49% | |
Investment Maturity Date | [2] | | | Jan. 19, 2017 | |
U.S. Treasury Bills, 0.485% due January 26, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [2] | | | 25.17% | |
Value | [2] | | | $ 113,970,018 | |
Principal Value | [2] | | | $ 114,000,000 | |
Investment Interest Rate | [2] | | | 0.485% | |
Investment Maturity Date | [2] | | | Jan. 26, 2017 | |
U.S. Treasury Bills, 0.490% due March 2, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [2] | | | 36.41% | |
Value | [2] | | | $ 164,873,775 | |
Principal Value | [2] | | | $ 165,000,000 | |
Investment Interest Rate | [2] | | | 0.49% | |
Investment Maturity Date | [2] | | | Mar. 2, 2017 | |
U.S. Treasury Bills, 0.530% due April 6, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [2] | | | 7.06% | |
Value | [2] | | | $ 31,956,864 | |
Principal Value | [2] | | | $ 32,000,000 | |
Investment Interest Rate | [2] | | | 0.53% | |
Investment Maturity Date | [2] | | | Apr. 6, 2017 | |
U.S. Treasury Bills, 0.625% due May 18, 2017 [Member] | | | | | |
Schedule of Investments [Line Items] | | | | | |
Percentage of Shareholders' Equity | [2],[8] | | | 18.73% | |
Value | [2],[8] | | | $ 84,809,005 | |
Principal Value | [2],[8] | | | $ 85,000,000 | |
Investment Interest Rate | [2],[8] | | | 0.625% | |
Investment Maturity Date | [2],[8] | | | May 18, 2017 | |
Restricted for maintenance margin | | | | $ 54,873,500 | |
| |
[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] | 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. | |
[3] | United States Treasury Obligations of $59,964,000 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] | 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 June 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 $54,873,500 are on deposit with the Commodity Broker and held as maintenance margin for open futures contracts. | |