Investments in Affiliates - Summary of Transactions in, and Earnings from, Investments in Affiliates (Detail) - USD ($)		12 Months Ended
		Dec. 31, 2021		Dec. 31, 2020		Dec. 31, 2019
Investments In And Advances To Affiliates [Line Items]
Beginning Value		$ 13,839,876		$ 4,434,970
Purchases at Cost				85,861,938
Proceeds from Sales				(76,457,032)
United States Treasury Obligations		(463)		(1,174)		$ 1,385
Ending Value		12,944,971		13,839,876		4,434,970
Dividend Income				21,085
Money Market Mutual Fund - Invesco Government & Agency Portfolio [Member] | Affiliated Investments [Member]
Investments In And Advances To Affiliates [Line Items]
Beginning Value	[1],[2]	13,839,876
Purchases at Cost		58,895,360		39,478,084
Proceeds from Sales		(59,790,265)		(25,638,208)
Ending Value		12,944,971	[3],[4]	13,839,876	[1],[2]
Dividend Income		$ 3,545		486
Money Market Mutual Fund - Invesco Premier U.S. Government Money Portfolio - Institutional Class [Member] | Affiliated Investments [Member]
Investments In And Advances To Affiliates [Line Items]
Beginning Value				4,434,970		3,829,452
Purchases at Cost				46,383,854		51,266,244
Proceeds from Sales				(50,818,824)		(50,660,726)
Ending Value						4,434,970
Dividend Income				$ 20,599		$ 49,044

[1] Affiliated issuer. The issuer and/or the Fund is a wholly-owned subsidiary of Invesco Ltd., or is affiliated by having an investment adviser that is under common control of Invesco Ltd. See Note 8

[2] The rate shown is the 7-day SEC standardized yield as of December 31, 2020.

[3] Affiliated issuer. The issuer and/or the Fund is a wholly-owned subsidiary of Invesco Ltd., or is affiliated by having an investment adviser that is under common control of Invesco Ltd. See Note 8.

[4] The rate shown is the 7-day SEC standardized yield as of December 31, 2021.