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

Settlement Agreement	12 Months Ended
Settlement Agreement	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Settlement Agreement	Settlement AgreementOn April 19, 2018, certain of the Company’s subsidiaries entered into settlement agreements with a third party arising from an interruption event not directly related to the Company’s business that the Company does not expect to reoccur (the “Settlement”). The Settlement provided for the Company’s subsidiaries to receive aggregate net payments of approximately $15.7 million in four equal installments between January 2019 and July 2020, in exchange for releasing and waiving all current and future claims against the third party. The Company recorded a pre-tax gain of $14.8 million during the fiscal year ended September 30, 2018 related to the Settlement. As of September 30, 2020, all amounts due pursuant to the Settlement have been received in full.