Document and Entity Information (USD $)
 12 Months Ended
Dec. 31, 2013
Jun. 30, 2013
Mar. 21, 2014
Common Class A
Mar. 21, 2014
Common Class B
Document Information [Line Items]        
Document Type 10-K      
Amendment Flag false      
Document Period End Date Dec. 31, 2013      
Document Fiscal Year Focus 2013      
Document Fiscal Period Focus FY      
Trading Symbol RGSE      
Entity Registrant Name Real Goods Solar, Inc.      
Entity Central Index Key 0001425565      
Current Fiscal Year End Date --12-31      
Entity Well-known Seasoned Issuer No      
Entity Current Reporting Status Yes      
Entity Voluntary Filers No      
Entity Filer Category Smaller Reporting Company      
Entity Common Stock, Shares Outstanding     44,946,489 0
Entity Public Float   $ 56,838,284