Quarterly report pursuant to Section 13 or 15(d)

Document and Entity Information

v3.8.0.1
Document and Entity Information - shares
6 Months Ended
Mar. 31, 2018
May 31, 2018
Document Information [Line Items]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Mar. 31, 2018  
Document Fiscal Year Focus 2018  
Document Fiscal Period Focus Q2  
Trading Symbol cik0001718227  
Entity Registrant Name Construction Partners, Inc.  
Entity Central Index Key 0001718227  
Current Fiscal Year End Date --09-30  
Entity Filer Category Non-accelerated Filer  
Common Class A [Member]    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   11,950,000
Common Class B [Member]    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   39,217,537