Investments in Affiliates -Summary of Transactions in, and Earnings from, Investments in Affiliates (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Investments in and Advances to Affiliates [Line Items]
Change in Unrealized Appreciation (Depreciation)	$ 30,428	$ (64,356)	$ (245,609)	$ 3,187
Dividend Income	2,941,478	4,942,778	5,209,447	13,271,950
Invesco Short Term Treasury ETF
Investments in and Advances to Affiliates [Line Items]
Investment Owned, at Fair Value, Beginning Balance		73,723,258		73,590,524
Change in Unrealized Appreciation (Depreciation)		(41,916)		90,818
Investment Owned, at Fair Value, Ending Balance		73,681,342		73,681,342
Dividend Income		808,028		1,515,794
Affiliated Investments [Member]
Investments in and Advances to Affiliates [Line Items]
Investment Owned, at Fair Value, Beginning Balance		559,836,326		983,150,588
Purchases at Cost		443,406,329		776,556,009
Proceeds from Sales		(687,781,359)		(1,444,378,035)
Change in Unrealized Appreciation (Depreciation)		(41,916)		90,818
Investment Owned, at Fair Value, Ending Balance		315,419,380		315,419,380
Dividend Income		4,942,778		13,271,950
Affiliated Investments [Member] | Invesco Government & Agency Portfolio, Institutional Class
Investments in and Advances to Affiliates [Line Items]
Investment Owned, at Fair Value, Beginning Balance		486,113,068		909,560,064
Purchases at Cost		443,406,329		776,556,009
Proceeds from Sales		(687,781,359)		(1,444,378,035)
Investment Owned, at Fair Value, Ending Balance		241,738,038		241,738,038
Dividend Income		$ 4,134,750		$ 11,756,156
Affiliated Investments [Member] | Money Market Mutual Fund - Invesco Government & Agency Portfolio, Institutional Class [Member]
Investments in and Advances to Affiliates [Line Items]
Investment Owned, at Fair Value, Beginning Balance	134,166,072		111,534,057
Purchases at Cost	258,294,906		489,138,943
Proceeds from Sales	(149,087,560)		(357,299,582)
Investment Owned, at Fair Value, Ending Balance	243,373,418		243,373,418
Dividend Income	$ 2,941,478		$ 5,209,447