Note 2 - Significant Accounting Policies - Activity in Gold Bullion (Details)	12 Months Ended
	Dec. 31, 2021 USD ($) oz		Dec. 31, 2020 USD ($) oz		Dec. 31, 2019 USD ($) oz
Beginning balance (Ounce) | oz	16,881,652		11,577,252		9,009,541
Beginning balance, average cost	$ 25,014,142,586		$ 15,094,673,874		$ 11,255,129,376
Beginning balance, fair value	$ 31,924,891,396	[1]	$ 17,632,155,037		$ 11,547,078,166
Gold bullion contributed (Ounce) | oz	1,010,824		6,866,938		3,668,032
Gold bullion contributed, average cost	$ 1,853,104,516		$ 12,103,493,289		$ 5,226,042,788
Gold bullion contributed, fair value	$ 1,853,104,516		$ 12,103,493,289		$ 5,226,042,788
Gold bullion distributed (Ounce) | oz	(2,067,597)		(1,527,240)		(1,075,809)
Gold bullion distributed, average cost	$ (3,083,787,949)		$ (2,134,454,305)		$ (1,355,372,636)
Gold bullion distributed, fair value	(3,649,216,540)		(2,617,761,048)		(1,418,257,979)
Gold bullion distributed, realized gain (loss)	$ 565,428,591		$ 483,306,743		$ 62,885,343
Gold bullion sold to pay expenses (Ounce) | oz	(40,554)		(35,298)		(24,512)
Gold bullion sold to pay expenses, average cost	$ (60,546,285)		$ (49,570,272)		$ (31,125,654)
Gold bullion sold to pay expenses, fair value	(73,370,533)		(62,451,444)		(34,028,445)
Gold bullion sold to pay expenses, realized gain (loss)	12,824,248		12,881,172		2,902,791
Net realized gain (loss), fair value	578,252,839		496,187,915		65,788,134
Net change in unrealized appreciation/depreciation, fair value	$ (1,904,612,983)		$ 4,373,267,647		$ 2,245,532,373
Ending balance (Ounce) | oz	15,784,325		16,881,652		11,577,252
Ending balance, average cost	$ 23,722,912,868		$ 25,014,142,586		$ 15,094,673,874
Ending balance, fair value	$ 28,729,048,695	[1]	$ 31,924,891,396	[1]	$ 17,632,155,037

[1] Cost of investment in gold bullion: $23,722,912,868 and $25,014,142,586, respectively.