Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
Revenue (Details) - USD ($) $ in Thousands	Sep. 27, 2025	Sep. 28, 2024	Sep. 30, 2023
Disaggregation of Revenue [Line Items]
Net sales	$ 1,480,099	$ 1,347,154	$ 1,132,793
Diesel buses
Disaggregation of Revenue [Line Items]
Net sales	523,371	461,222	341,969
Alternative fuel buses
Disaggregation of Revenue [Line Items]
Net sales	798,415	726,083	648,900
Other
Disaggregation of Revenue [Line Items]
Net sales	58,072	58,074	46,246
Parts
Disaggregation of Revenue [Line Items]
Net sales	$ 100,241	$ 101,775	$ 95,678

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

Blue Bird Corp 10-K