v3.19.3
Document and Entity Information - shares
9 Months Ended
Sep. 30, 2019
Nov. 12, 2019
Document and Entity Information [Abstract]    
Entity Registrant Name Infrastructure & Energy Alternatives, Inc.  
Entity Central Index Key 0001652362  
Document Type 10-Q  
Document Period End Date Sep. 30, 2019  
Document Fiscal Year Focus 2019  
Amendment Flag false  
Document Fiscal Period Focus Q3  
Current Fiscal Year End Date --12-31  
Entity Filer Category Accelerated Filer  
Entity Emerging Growth Company true  
Entity Ex Transition Period false  
Entity Small Business true  
Entity Current Reporting Status Yes  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   22,252,489