Investments in Affiliates - Summary of Transactions in, and Earnings from, Investments in Affiliates (Excluding Affiliated Money Market Funds) (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Investments In And Advances To Affiliates [Line Items]
Beginning Value	$ 1,692,470,773
Change in Unrealized Appreciation (Depreciation)	(353,565)	$ 336,743	$ 428,208
Ending Value	1,269,897,511	1,692,470,773
Dividend Income	46,006,931	61,814,575	31,109,319
Investment, Affiliated Issuer [Member]
Investments In And Advances To Affiliates [Line Items]
Beginning Value	908,120,125
Ending Value	876,644,367	908,120,125
Affiliated Investments [Member]
Investments In And Advances To Affiliates [Line Items]
Purchases at Cost	2,207,958,507	3,555,261,081	7,464,209,086
Proceeds from Sales	(2,239,424,067)	(4,072,945,337)	(8,042,449,383)
Change in Unrealized Appreciation (Depreciation)	(10,198)	453,841	(522,617)
Realized Gain (Loss)			(103,308)
Affiliated Investments [Member] | Investment, Affiliated Issuer [Member]
Investments In And Advances To Affiliates [Line Items]
Beginning Value	908,120,125	1,425,350,540	2,004,216,762
Ending Value	876,644,367	908,120,125	1,425,350,540
Dividend Income	46,006,931	61,814,575	31,109,319
Affiliated Investments [Member] | Invesco Government & Agency Portfolio, Institutional Class [Member]
Investments In And Advances To Affiliates [Line Items]
Purchases at Cost	2,207,958,507	3,481,583,930	7,443,115,283
Proceeds from Sales	(2,239,424,067)	(4,072,945,337)	(7,970,371,224)
Affiliated Investments [Member] | Invesco Government & Agency Portfolio, Institutional Class [Member] | Investment, Affiliated Issuer [Member]
Investments In And Advances To Affiliates [Line Items]
Beginning Value	692,738,727	1,284,100,134	1,811,356,075
Ending Value	661,273,167	692,738,727	1,284,100,134
Dividend Income	35,263,436	53,660,273	28,222,082
Affiliated Investments [Member] | Invesco Short Term Treasury ETF [Member]
Investments In And Advances To Affiliates [Line Items]
Purchases at Cost		73,677,151	21,093,803
Proceeds from Sales			(72,078,159)
Change in Unrealized Appreciation (Depreciation)	(10,198)	453,841	(522,617)
Realized Gain (Loss)			(103,308)
Affiliated Investments [Member] | Invesco Short Term Treasury ETF [Member] | Investment, Affiliated Issuer [Member]
Investments In And Advances To Affiliates [Line Items]
Beginning Value	215,381,398	141,250,406	192,860,687
Ending Value	215,371,200	215,381,398	141,250,406
Dividend Income	$ 10,743,495	$ 8,154,302	$ 2,887,237