Construction Partners, Inc. Annual report pursuant to Section 13 and 15(d)

COVID-19 Pandemic	12 Months Ended
COVID-19 Pandemic	Sep. 30, 2021
Unusual or Infrequent Items, or Both [Abstract]
COVID-19 Pandemic	COVID-19 PandemicThe Company is closely monitoring the impact of the COVID-19 pandemic on all aspects of its business, including how it has impacted and may continue to impact the Company’s customers, employees, suppliers, and vendors. While the Company did not incur significant disruptions in its operations from the COVID-19 pandemic during the fiscal year ended September 30, 2021, due to the uncertainties surrounding the COVID-19 pandemic, it is unable to predict the impact that the COVID-19 pandemic will have on its financial position, operating results and cash flows in future periods.As the Company continues to monitor the impacts of the pandemic on its financial position, operating results, and cash flows, it will consider and evaluate the need for any additional workforce actions in future periods. The Company is monitoring the executive order requiring vaccinations for certain employees of federal contractors and the emergency temporary standard issued by OSHA mandating vaccination or testing and masking requirements for companies with more than 100 employees.