Document and Entity Information
 3 Months Ended
Mar. 31, 2013
May 10, 2013
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Mar. 31, 2013  
Trading Symbol htm  
Entity Registrant Name US GEOTHERMAL INC  
Entity Central Index Key 0001172136  
Current Fiscal Year End Date --03-31  
Entity Filer Category Smaller Reporting Company  
Entity Common Stock, Shares Outstanding   101,516,764
Entity Current Reporting Status Yes  
Entity Voluntary Filers No  
Entity Well Known Seasoned Issuer No  
Document Fiscal Year Focus 2013  
Document Fiscal Period Focus Q1