Investments in Affiliates - Summary of Transactions in, and Earnings from, Investments in Affiliates (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2022		Mar. 31, 2021
Investments In And Advances To Affiliates [Line Items]
Beginning Value	$ 71,801,967
Change in Unrealized Appreciation (Depreciation)	(13,575)		$ 3,898
Ending Value	191,710,318
Affiliated Investments [Member]
Investments In And Advances To Affiliates [Line Items]
Beginning Value	71,801,967		38,268,976
Purchases at Cost	181,901,978		51,796,508
Proceeds from Sales	(61,986,487)		(39,062,237)
Change in Unrealized Appreciation (Depreciation)	(7,140)		1,428
Ending Value	191,710,318		51,004,675
Dividend Income	22,946		4,427
Affiliated Investments [Member] | Exchange Traded Funds
Investments In And Advances To Affiliates [Line Items]
Beginning Value	10,055,500	[1]	10,059,784
Change in Unrealized Appreciation (Depreciation)	(7,140)		1,428
Ending Value	10,048,360	[1]	10,061,212
Dividend Income	605		1,497
Affiliated Investments [Member] | Money Market Mutual Fund - Invesco Government & Agency Portfolio, Institutional Class [Member]
Investments In And Advances To Affiliates [Line Items]
Beginning Value	61,746,467		28,209,192
Purchases at Cost	181,901,978		51,796,508
Proceeds from Sales	(61,986,487)		(39,062,237)
Ending Value	181,661,958		40,943,463
Dividend Income	$ 22,341		$ 2,930

[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.