Note 11 - Financial Information by Business Segment (Details Textual) - USD ($)	3 Months Ended		9 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Statement [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 3,624,000	$ 6,175,000	$ 11,764,000	$ 19,270,000
Investment Management Services [Member]
Statement [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	3,624,000	6,175,000	11,764,000	19,270,000
Investment Management Services [Member] | U S Global Investors Funds [Member]
Statement [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	482,000	803,000	1,400,000	3,100,000
Investment Management Services [Member] | U S Global E T Fs [Member]
Statement [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 3,100,000	$ 5,400,000	$ 10,400,000	$ 16,100,000