Investment in Gold (Details) - Ounces of Gold [Member]	12 Months Ended
	Jan. 31, 2020 USD ($) Ounces	Jan. 31, 2019 USD ($) Ounces	Jan. 31, 2018 USD ($) Ounces
Changes In Ounces Of Gold And Fair Value [Line Items]
Beginning balance | Ounces	116,515	105,697	101,789
Gold bullion contributed | Ounces	12,719	14,257	5,431
Gold bullion distributed | Ounces	(3,947)	(3,439)	(1,523)
Realized gain (loss) from gold distributed from in-kind | Ounces
Change in unrealized appreciation | Ounces
Ending balance | Ounces	125,287	116,515	105,697
Changes in fair value of gold and fair value
Beginning balance, Fair Value | $	$ 154,177,919	$ 142,168,257	$ 123,449,687
Gold bullion contributed, Fair Value | $	18,920,998	18,490,428	6,924,438
Gold bullion distributed, Fair Value | $	(5,019,758)	(4,136,765)	(1,915,670)
Realized gain (loss) from gold distributed from in-kind, Fair Value | $	96,601	(148,638)	29,173
Change in unrealized appreciation (depreciation), Fair Value | $	30,303,992	(2,195,363)	13,680,629
Ending balance, Fair Value | $	$ 198,479,752	$ 154,177,919	$ 142,168,257