Accounting Policies, by Policy (Policies)	9 Months Ended
Mar. 31, 2017
Accounting Policies [Abstract]
Basis of Accounting, Policy [Policy Text Block]	U.S. Global Investors, Inc. (the “Company” or “U.S. Global”) has prepared the consolidated financial statements pursuant to accounting principles generally accepted in the United States of America (“U.S. GAAP”) and the rules and regulations of the United States Securities and Exchange Commission (“SEC”) that permit reduced disclosure for interim periods. The financial information included herein reflects all adjustments (consisting solely of normal recurring adjustments), which are, in management’s opinion, necessary for a fair presentation of results for the interim periods presented. The Company has consistently followed the accounting policies set forth in the notes to the consolidated financial statements in the Company’s Form 10-K for the fiscal year ended June 30, 2016, except for the adoption of new accounting pronouncements discussed below. The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries, U.S. Global Brokerage, Inc., U.S. Global Investors (Bermuda) Limited, U.S. Global Investors (Canada) Limited (“USCAN”), and U.S. Global Indices, LLC, and its 65 percent interest in Galileo Global Equity Advisor Inc. (“Galileo”). U.S. Global Brokerage, Inc. ceased operations in December 2015 as discussed in Note 12. Galileo is consolidated with the operations of the Company. The non-controlling interest in this subsidiary is included in “non-controlling interest in subsidiary” in the equity section of the Consolidated Balance Sheets. Frank Holmes, CEO, and Susan McGee, President and General Counsel, serve as directors of Galileo. The Company’s evaluation for consolidation includes whether entities in which it has an interest or from which it receives fees are variable interest entities (“VIEs”) and whether the Company is the primary beneficiary of any VIEs identified in its analysis. A VIE is an entity in which either (a) the equity investment at risk is not sufficient to permit the entity to finance its own activities without additional financial support or (b) the group of holders of the equity investment at risk lack certain characteristics of a controlling financial interest. The primary beneficiary is the entity that has the obligation to absorb a majority of the expected losses or the right to receive the majority of the residual returns and consolidates the VIE on the basis of having a controlling financial interest. The Company holds variable interests in, but is not deemed to be the primary beneficiary of, certain funds it advises. The Company’s interests in these VIEs consist of the Company’s direct ownership therein and any fees earned but uncollected. In the ordinary course of business, the Company may choose to waive certain fees or assume operating expenses of the funds it advises for competitive, regulatory or contractual reasons (see Note 3 for information regarding fee waivers). The Company has not provided financial support to any of these entities outside the ordinary course of business. The Company’s risk of loss with respect to these VIEs is limited to the carrying value of its investments in, and fees receivable from, the entities. The Company does not consolidate these VIEs because it is not the primary beneficiary. The Company’s total exposure to unconsolidated VIEs, consisting of the carrying value of investment securities and receivables for fees, was $11.4 million at March 31, 2017, and $11.8 million at June 30, 2016. All significant intercompany balances and transactions have been eliminated in consolidation. Certain amounts have been reclassified for comparative purposes. The results of operations for the nine months ended March 31, 2017, are not necessarily indicative of the results to be expected for the entire year. The unaudited interim financial information in these condensed financial statements should be read in conjunction with the consolidated financial statements contained in the Company’s annual report.
New Accounting Pronouncements, Policy [Policy Text Block]	Recent Accounting Pronouncements Accounting Pronouncements Adopted During the Period In February 2015, the FASB issued Accounting Standards Update (“ASU”) 2015-02, Amendments to the Consolidation Analysis (“ASU 2015-02”), which amends the consolidation requirements in ASC 810, Consolidation. This standard modifies existing consolidation guidance for reporting organizations that are required to evaluate whether they should consolidate certain legal entities. ASU 2015-02 is effective for fiscal years and interim periods within those years beginning after December 15, 2015, and requires either a retrospective or a modified retrospective approach to adoption. The Company adopted this standard on a modified retrospective approach effective July 1, 2016. The adoption did not result in any change in consolidated entities. See further discussion of the Company’s analysis for consolidation in Note 1, Basis of Presentation. In May 2015, the FASB issued ASU 2015-07, Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent) (“ASU 2015-07”). ASU 2015-07 removes the requirement to categorize within the fair value hierarchy all investments for which fair value is measured using the NAV per share practical expedient. The update is effective for interim and annual reporting periods in fiscal years beginning after December 15, 2015, and requires the retrospective adoption approach. The Company adopted this standard for the September 30, 2016, financial statements on a retrospective basis and modified the presentation of the fair value hierarchy tables included in the notes to financial statements. In November 2015, the FASB issued ASU 2015-17, Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes (“ASU 2015-17”). ASU 2015-17 requires entities to present deferred tax assets and deferred tax liabilities as noncurrent in a classified balance sheet. It simplifies the current guidance, which requires entities to separately present deferred tax assets and liabilities as current or noncurrent in a classified balance sheet. Netting by tax jurisdiction is still required under the new guidance. The update is effective for annual periods beginning after December 15, 2016, and interim periods within those annual periods, and early adoption is permitted. Entities are permitted to apply the amendments either prospectively or retrospectively. The Company early adopted this guidance effective September 30, 2016, on a prospective basis. As a full reserve valuation allowance is recorded for deferred tax balances, adoption of the guidance did not result in any changes or reclassifications in the Consolidated Balance Sheets as of September 30, 2016. No prior periods were retrospectively adjusted. Accounting Pronouncements Not Yet Adopted In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”), which supersedes nearly all existing revenue recognition guidance under U.S. GAAP. The core principle of ASU 2014-09 is to recognize revenues when promised goods or services are transferred to customers in an amount that reflects the consideration to which an entity expects to be entitled for those goods or services. ASU 2014-09 defines a five-step process to achieve this core principle and, in doing so, more judgment and estimates may be required within the revenue recognition process than are required under existing U.S. GAAP. The standard will be effective for annual reporting periods beginning after December 15, 2017, and interim periods therein. Early adoption is permitted, but the Company currently does not expect to implement the new standard before the required effective date. The standard allows adoption using either of the following transition methods: (i) a full retrospective approach reflecting the application of the standard in each prior reporting period with the option to elect certain practical expedients, or (ii) a retrospective approach with the cumulative effect of initially adopting ASU 2014-09 recognized at the date of adoption (which includes additional footnote disclosures). Management has not yet determined the method by which it will adopt the standard. The Company is in the process of evaluating its contracts using the prescribed five-step process to determine the impact of this standard and does not currently expect the adoption to have a material impact on its consolidated financial statements. In August 2014, the FASB issued ASU 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern (“ASU 2014-15”). This update requires an entity’s management to evaluate whether there are conditions or events, considered in the aggregate, that raise substantial doubt about the entity’s ability to continue as a going concern within one year after the date that the financial statements are issued (or within one year after the date that the financial statements are available to be issued when applicable). When conditions or events raise substantial doubts about an entity’s ability to continue as a going concern, management shall disclose: i) the principal conditions or events that raise substantial doubt about the entity’s ability to continue as a going concern; ii) management’s evaluation of the significance of those conditions or events in relation to the entity’s ability to meet its obligations; and iii) management’s plans that are intended to mitigate the conditions or events - and whether or not those plans alleviate the substantial doubt about the entity’s ability to continue as a going concern. ASU 2014-15 is effective for the annual period ending after December 15, 2016, and for annual period and interim periods thereafter. Early application is permitted. Management does not currently anticipate that this update will have any impact on the Company’s financial statement disclosures. In January 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities (“ASU 2016-01”). ASU 2016-01 amends the guidance on the classification and measurement of investments in equity securities. It also amends certain presentation and disclosure requirements. Under the amended guidance, all equity investments in unconsolidated entities (other than those accounted for using the equity method of accounting) will generally be measured at fair value through earnings. There will no longer be an available-for-sale classification (changes in fair value reported in other comprehensive income) for equity securities with readily determinable fair values. ASU 2016-01 is effective for public business entities for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. As indicated, when this standard is adopted, changes in the fair value of the Company’s investments securities classified as available-for-sale will no longer be reported through other comprehensive income, but rather through earnings, causing our investment income (loss) to be more volatile. The Company is currently evaluating other potential impacts of this standard on its consolidated financial statements. In February 2016, the FASB issued ASU 2016-02, Leases (“ASU 2016-02”). ASU 2016-02 introduces a lessee model that brings most leases on the balance sheet. The new guidance will be effective for public business entities for annual periods beginning after December 15, 2018, and interim periods therein. Early adoption is permitted. The Company’s current leases are primarily for equipment and for office space for the Canadian subsidiary. The Company is currently evaluating the potential impact of this standard on its consolidated financial statements. In March 2016, the FASB issued ASU 2016-08, Revenue from Contracts from Customers - Principal versus Agent Considerations (Reporting Revenue Gross versus Net) (“ASU 2016-08”). ASU 2016-08 amends the guidance in ASU 2014-09, which is not yet effective. Among other things, the ASU clarifies that an entity should evaluate whether it is the principal or the agent for each specified good or service promised in a contract with a customer. The effective date and transition requirements for the amendments in ASU 2016-08 are the same as the effective date and transition requirements of ASU 2014-09. The Company is evaluating the effect of this ASU in conjunction with the evaluation of ASU 2014-09. In March 2016, the FASB issued ASU 2016-09, Improvements to Employee Share-Based Payment Accounting (“ASU 2016-09”). ASU 2016-09 includes provisions intended to simplify various aspects related to how share-based payments are accounted for and disclosed. ASU 2016-09 is effective for public business entities for annual reporting periods beginning after December 15, 2016, and interim periods within those annual periods. Early adoption will be permitted in any interim or annual period, as long as all elements of the new standard are adopted at the same time. Management currently does not expect to implement the new standard before the required effective date. The Company is currently evaluating the potential impact of this standard but does not currently expect the adoption to have a material impact on its consolidated financial statements. In June 2016, the FASB issued 2016-13, Financial Instruments – Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”). ASU 2016-13 adds to U.S. GAAP an impairment model (known as the current expected credit loss (CECL) model) that is based on expected losses rather than incurred losses. Under the new guidance, an entity recognizes as an allowance its estimate of expected credit losses. ASU 2016-13 is effective for public business entities that are SEC filers for fiscal years beginning after December 15, 2019, including interim periods within those years. Earlier application is permitted only for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. The Company is currently evaluating the potential impact of this standard on its consolidated financial statements. In August 2016, the FASB issued 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments (“ASU 2016-15”). ASU 2016-15 may change how an entity classifies certain cash receipts and cash payments on its statement of cash flows to reduce existing diversity in practice. The guidance will generally be applied retrospectively and is effective for public business entities for fiscal years beginning after December 15, 2017, and interim periods within those years. Early adoption is permitted, and the Company is in the process of determining whether the standard will be early adopted. The Company is currently evaluating the potential impact of this standard but does not currently expect the adoption to have a material impact on the consolidated statements of cash flows. In November 2016, the FASB issued 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash (“ASU 2016-18”). Under ASU 2016-18, restricted cash and restricted cash equivalents will be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. ASU 2016-18 is effective for public business entities for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. The guidance will be applied retrospectively, and early adoption is permitted. The Company is in the process of determining whether the standard will be early adopted.

Recent Accounting Pronouncements

Accounting Pronouncements Adopted During the Period

In February 2015, the FASB issued Accounting Standards Update (“ASU”) 2015-02, Amendments to the Consolidation Analysis (“ASU 2015-02”), which amends the consolidation requirements in ASC 810, Consolidation. This standard modifies existing consolidation guidance for reporting organizations that are required to evaluate whether they should consolidate certain legal entities. ASU 2015-02 is effective for fiscal years and interim periods within those years beginning after December 15, 2015, and requires either a retrospective or a modified retrospective approach to adoption. The Company adopted this standard on a modified retrospective approach effective July 1, 2016. The adoption did not result in any change in consolidated entities. See further discussion of the Company’s analysis for consolidation in Note 1, Basis of Presentation.

In May 2015, the FASB issued ASU 2015-07, Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent) (“ASU 2015-07”). ASU 2015-07 removes the requirement to categorize within the fair value hierarchy all investments for which fair value is measured using the NAV per share practical expedient. The update is effective for interim and annual reporting periods in fiscal years beginning after December 15, 2015, and requires the retrospective adoption approach. The Company adopted this standard for the September 30, 2016, financial statements on a retrospective basis and modified the presentation of the fair value hierarchy tables included in the notes to financial statements.

In November 2015, the FASB issued ASU 2015-17, Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes (“ASU 2015-17”). ASU 2015-17 requires entities to present deferred tax assets and deferred tax liabilities as noncurrent in a classified balance sheet. It simplifies the current guidance, which requires entities to separately present deferred tax assets and liabilities as current or noncurrent in a classified balance sheet. Netting by tax jurisdiction is still required under the new guidance. The update is effective for annual periods beginning after December 15, 2016, and interim periods within those annual periods, and early adoption is permitted. Entities are permitted to apply the amendments either prospectively or retrospectively. The Company early adopted this guidance effective September 30, 2016, on a prospective basis. As a full reserve valuation allowance is recorded for deferred tax balances, adoption of the guidance did not result in any changes or reclassifications in the Consolidated Balance Sheets as of September 30, 2016. No prior periods were retrospectively adjusted.

Accounting Pronouncements Not Yet Adopted

In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”), which supersedes nearly all existing revenue recognition guidance under U.S. GAAP. The core principle of ASU 2014-09 is to recognize revenues when promised goods or services are transferred to customers in an amount that reflects the consideration to which an entity expects to be entitled for those goods or services. ASU 2014-09 defines a five-step process to achieve this core principle and, in doing so, more judgment and estimates may be required within the revenue recognition process than are required under existing U.S. GAAP. The standard will be effective for annual reporting periods beginning after December 15, 2017, and interim periods therein. Early adoption is permitted, but the Company currently does not expect to implement the new standard before the required effective date. The standard allows adoption using either of the following transition methods: (i) a full retrospective approach reflecting the application of the standard in each prior reporting period with the option to elect certain practical expedients, or (ii) a retrospective approach with the cumulative effect of initially adopting ASU 2014-09 recognized at the date of adoption (which includes additional footnote disclosures). Management has not yet determined the method by which it will adopt the standard. The Company is in the process of evaluating its contracts using the prescribed five-step process to determine the impact of this standard and does not currently expect the adoption to have a material impact on its consolidated financial statements.

In August 2014, the FASB issued ASU 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern (“ASU 2014-15”). This update requires an entity’s management to evaluate whether there are conditions or events, considered in the aggregate, that raise substantial doubt about the entity’s ability to continue as a going concern within one year after the date that the financial statements are issued (or within one year after the date that the financial statements are available to be issued when applicable). When conditions or events raise substantial doubts about an entity’s ability to continue as a going concern, management shall disclose: i) the principal conditions or events that raise substantial doubt about the entity’s ability to continue as a going concern; ii) management’s evaluation of the significance of those conditions or events in relation to the entity’s ability to meet its obligations; and iii) management’s plans that are intended to mitigate the conditions or events - and whether or not those plans alleviate the substantial doubt about the entity’s ability to continue as a going concern. ASU 2014-15 is effective for the annual period ending after December 15, 2016, and for annual period and interim periods thereafter. Early application is permitted. Management does not currently anticipate that this update will have any impact on the Company’s financial statement disclosures.

In January 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities (“ASU 2016-01”). ASU 2016-01 amends the guidance on the classification and measurement of investments in equity securities. It also amends certain presentation and disclosure requirements. Under the amended guidance, all equity investments in unconsolidated entities (other than those accounted for using the equity method of accounting) will generally be measured at fair value through earnings. There will no longer be an available-for-sale classification (changes in fair value reported in other comprehensive income) for equity securities with readily determinable fair values. ASU 2016-01 is effective for public business entities for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. As indicated, when this standard is adopted, changes in the fair value of the Company’s investments securities classified as available-for-sale will no longer be reported through other comprehensive income, but rather through earnings, causing our investment income (loss) to be more volatile. The Company is currently evaluating other potential impacts of this standard on its consolidated financial statements.

In February 2016, the FASB issued ASU 2016-02, Leases (“ASU 2016-02”). ASU 2016-02 introduces a lessee model that brings most leases on the balance sheet. The new guidance will be effective for public business entities for annual periods beginning after December 15, 2018, and interim periods therein. Early adoption is permitted. The Company’s current leases are primarily for equipment and for office space for the Canadian subsidiary. The Company is currently evaluating the potential impact of this standard on its consolidated financial statements.

In March 2016, the FASB issued ASU 2016-08, Revenue from Contracts from Customers - Principal versus Agent Considerations (Reporting Revenue Gross versus Net) (“ASU 2016-08”). ASU 2016-08 amends the guidance in ASU 2014-09, which is not yet effective. Among other things, the ASU clarifies that an entity should evaluate whether it is the principal or the agent for each specified good or service promised in a contract with a customer. The effective date and transition requirements for the amendments in ASU 2016-08 are the same as the effective date and transition requirements of ASU 2014-09. The Company is evaluating the effect of this ASU in conjunction with the evaluation of ASU 2014-09.

In March 2016, the FASB issued ASU 2016-09, Improvements to Employee Share-Based Payment Accounting (“ASU 2016-09”). ASU 2016-09 includes provisions intended to simplify various aspects related to how share-based payments are accounted for and disclosed. ASU 2016-09 is effective for public business entities for annual reporting periods beginning after December 15, 2016, and interim periods within those annual periods. Early adoption will be permitted in any interim or annual period, as long as all elements of the new standard are adopted at the same time. Management currently does not expect to implement the new standard before the required effective date. The Company is currently evaluating the potential impact of this standard but does not currently expect the adoption to have a material impact on its consolidated financial statements.

In June 2016, the FASB issued 2016-13, Financial Instruments – Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”). ASU 2016-13 adds to U.S. GAAP an impairment model (known as the current expected credit loss (CECL) model) that is based on expected losses rather than incurred losses. Under the new guidance, an entity recognizes as an allowance its estimate of expected credit losses. ASU 2016-13 is effective for public business entities that are SEC filers for fiscal years beginning after December 15, 2019, including interim periods within those years. Earlier application is permitted only for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. The Company is currently evaluating the potential impact of this standard on its consolidated financial statements.

In August 2016, the FASB issued 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments (“ASU 2016-15”). ASU 2016-15 may change how an entity classifies certain cash receipts and cash payments on its statement of cash flows to reduce existing diversity in practice. The guidance will generally be applied retrospectively and is effective for public business entities for fiscal years beginning after December 15, 2017, and interim periods within those years. Early adoption is permitted, and the Company is in the process of determining whether the standard will be early adopted. The Company is currently evaluating the potential impact of this standard but does not currently expect the adoption to have a material impact on the consolidated statements of cash flows.

In November 2016, the FASB issued 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash (“ASU 2016-18”). Under ASU 2016-18, restricted cash and restricted cash equivalents will be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. ASU 2016-18 is effective for public business entities for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. The guidance will be applied retrospectively, and early adoption is permitted. The Company is in the process of determining whether the standard will be early adopted.