Construction Partners, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Related Parties - Additional Information (Detail)

v3.8.0.1

Related Parties - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Sep. 30, 2017
Related Party Transaction [Line Items]
Cost of revenues	$ 105,150,000	$ 96,005,000	$ 232,773,000	$ 199,396,000
Accounts payable	37,324,000		37,324,000			$ 52,402,000
Related Parties [Member]
Related Party Transaction [Line Items]
Note receivable as consideration for sale of the wholly-owned subsidiary					$ 1,000,000
Related Parties [Member] \| Construction Services One [Member]
Related Party Transaction [Line Items]
Revenue	300,000	700,000	1,500,000	1,800,000
Contract receivable	4,600,000		4,600,000			5,300,000
Related Parties [Member] \| Construction Services Two [Member]
Related Party Transaction [Line Items]
Revenue	100,000	0	200,000	0
Contract receivable	600,000		600,000			1,000,000
Austin Trucking [Member]
Related Party Transaction [Line Items]
Cost of revenues	1,400,000	1,500,000	4,300,000	4,400,000
Accounts payable	500,000		500,000			$ 1,000,000
SunTx [Member] \| Management Service Agreement [Member]
Related Party Transaction [Line Items]
Related party expense	250,000
Payment to related party	300,000	$ 400,000	700,000	$ 700,000
SunTx [Member] \| Management Service Agreement [Member] \| Other Noncurrent Assets [Member]
Related Party Transaction [Line Items]
Related party expense	100,000
Accounts Payable [Member] \| Related Parties [Member]
Related Party Transaction [Line Items]
Note receivable as consideration for sale of the wholly-owned subsidiary	$ 900,000		$ 900,000

- Definition

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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