| Document And Entity Information - USD ($) | Jun. 30, 2022 | Aug. 19, 2022 | Dec. 31, 2021 |
| Document Information [Line Items] | |||
| Entity, Registrant Name | U.S. GLOBAL INVESTORS, INC. | ||
| Document, Type | 10-K/A | ||
| Document, Annual Report | true | ||
| Document, Period End Date | Jun. 30, 2022 | ||
| Current Fiscal Year End Date | --06-30 | ||
| Document, Fiscal Period Focus | FY | ||
| Document, Fiscal Year Focus | 2021 | ||
| Document, Transition Report | false | ||
| Entity, File Number | 0-13928 | ||
| Entity, Incorporation, State or Country Code | TX | ||
| Entity, Tax Identification Number | 74-1598370 | ||
| Entity, Address, Address Line One | 7900 Callaghan Road | ||
| Entity, Address, City or Town | San Antonio | ||
| Entity, Address, State or Province | TX | ||
| Entity, Address, Postal Zip Code | 78229 | ||
| City Area Code | 210 | ||
| Local Phone Number | 308-1234 | ||
| Title of 12(b) Security | Class A common stock | ||
| Trading Symbol | GROW | ||
| Security Exchange Name | NASDAQ | ||
| Entity, Well-known Seasoned Issuer | No | ||
| Entity, Voluntary Filers | No | ||
| Entity, Current Reporting Status | Yes | ||
| Entity, Interactive Data, Current | Yes | ||
| Entity, Filer Category | Non-accelerated Filer | ||
| Entity, Small Business | true | ||
| Entity, Emerging Growth Company | false | ||
| ICFR Auditor Attestation Flag | false | ||
| Entity, Shell Company | false | ||
| Entity, Public Float | $ 51,433,655 | ||
| Auditor Name | BDO USA, LLP | ||
| Auditor Location | Dallas, Texas | ||
| Auditor Firm ID | 243 | ||
| Amendment Description | We are filing this Amendment No. 1 (this “Amendment”) to our Annual Report on Form 10-K for the year ended June 30, 2022, as filed with the Securities and Exchange Commission on September 1, 2022 (the “Original Form 10-K”). The purpose of this Amendment is to correct the shares of registrant's class A nonvoting common stock issued and outstanding and the shares of registrant's class C voting common stock issued and outstanding number as of August 19, 2022, on the cover page and within Item 12. In accordance with Rule 12b-15 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), Item 9A of Part II, Item 12 of Part III, and Item 15(a)3 of Part IV of the Original Form 10-K is hereby amended and restated in its entirety. In addition, as required by the Exchange Act, new certifications by our principal executive officer and principal financial officer are filed herewith as exhibits to this Amendment pursuant to Rule 13a-14(a) of the Exchange Act. Except as described above, no other changes have been made to the Original Form 10-K, and this Amendment does not amend, update, or change any other items or disclosures in the Original Form 10-K. This Amendment does not reflect subsequent events occurring after the filing date of the Original Form 10-K or modify or update in any way disclosures in the Original Form 10-K. This Amended Annual Report on Form 10-K/A reflects amendments to the following items: • Cover Page • Part II, Item 9A — Controls and Procedures • Part III, Item 12 — Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters • Part IV, Item 15 (a) 3 — Exhibits The Company's Chief Executive Officer and Chief Financial Officer are providing currently dated certifications in connection with this Amended Annual Report on Form 10-K/A. See Exhibit 31.2. | ||
| Amendment Flag | true | ||
| Entity, Central Index Key | 0000754811 | ||
| Common Class A [Member] | |||
| Document Information [Line Items] | |||
| Entity, Common Stock Shares, Outstanding | 12,884,169 | ||
| Common Class C [Member] | |||
| Document Information [Line Items] | |||
| Entity, Common Stock Shares, Outstanding | 2,068,549 |
