Accounts Receivable, net	12 Months Ended
Sep. 30, 2025
Receivables [Abstract]
Accounts Receivable, net	5. Accounts Receivable, net Accounts receivable of $393.1 and $415.2, is net of an allowance for doubtful accounts of $9.8 and $10.0 and includes amounts of retention on incomplete projects of $58.3 and $65.7 at September 30, 2025 and September 30, 2024, respectively, which are generally expected to be collected within one year.

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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