Accounts Receivable, net	12 Months Ended
Sep. 30, 2023
Receivables [Abstract]
Accounts Receivable, net	5. Accounts Receivable, net Accounts receivable of $442.3 and $397.6, is net of an allowance for doubtful accounts of $5.1 and $4.0 and includes amounts of retention on incomplete projects to be completed within one year of $58.7 and $48.8 at September 30, 2023 and September 30, 2022, respectively.

The entire disclosure for accounts receivable, contract receivable, receivable held-for-sale, and nontrade receivable.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//310/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//326/tableOfContent

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