XML 10 R1.htm IDEA: XBRL DOCUMENT v3.10.0.1
Document And Entity Information - shares
 6 Months Ended
Dec. 31, 2018
Jan. 28, 2019
Document Information [Line Items]    
Entity Registrant Name U S GLOBAL INVESTORS INC  
Document Type 10-Q  
Current Fiscal Year End Date --06-30  
Amendment Flag false  
Entity Central Index Key 0000754811  
Entity Current Reporting Status Yes  
Entity Filer Category Non-accelerated Filer  
Document Period End Date Dec. 31, 2018  
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q2  
Entity Small Business true  
Entity Emerging Growth Company false  
Entity Ex Transition Period false  
Common Class B [Member]    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   0
Common Class A [Member]    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   13,067,537
Common Class C [Member]    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   2,068,857