| | | | | | | | | | | | | | | | | | | | | |
<?xml version="1.0" encoding="windows-1252"?> |
<FilingSummary> |
| <Version> 3.20.2 </Version> |
| <ProcessingTime/> |
| <ReportFormat> html </ReportFormat> |
| <ContextCount> 164 </ContextCount> |
| <ElementCount> 299 </ElementCount> |
| <EntityCount> 1 </EntityCount> |
| <FootnotesReported> false </FootnotesReported> |
| <SegmentCount> 39 </SegmentCount> |
| <ScenarioCount> 0 </ScenarioCount> |
| <TuplesReported> false </TuplesReported> |
| <UnitCount> 5 </UnitCount> |
| <MyReports> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R1.htm </HtmlFileName> |
| | | <LongName> 0001000 - Document - Document and Entity Information </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/DocumentAndEntityInformation </Role> |
| | | <ShortName> Document and Entity Information </ShortName> |
| | | <MenuCategory> Cover </MenuCategory> |
| | | <Position> 1 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R2.htm </HtmlFileName> |
| | | <LongName> 1001000 - Statement - Condensed Consolidated Balance Sheets </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/CondensedConsolidatedBalanceSheets </Role> |
| | | <ShortName> Condensed Consolidated Balance Sheets </ShortName> |
| | | <MenuCategory> Statements </MenuCategory> |
| | | <Position> 2 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R3.htm </HtmlFileName> |
| | | <LongName> 1001501 - Statement - Condensed Consolidated Balance Sheets (Parenthetical) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/CondensedConsolidatedBalanceSheetsParenthetical </Role> |
| | | <ShortName> Condensed Consolidated Balance Sheets (Parenthetical) </ShortName> |
| | | <MenuCategory> Statements </MenuCategory> |
| | | <Position> 3 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R4.htm </HtmlFileName> |
| | | <LongName> 1002000 - Statement - Condensed Consolidated Statements of Operations </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/CondensedConsolidatedStatementsOfOperations </Role> |
| | | <ShortName> Condensed Consolidated Statements of Operations </ShortName> |
| | | <MenuCategory> Statements </MenuCategory> |
| | | <Position> 4 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R5.htm </HtmlFileName> |
| | | <LongName> 1003000 - Statement - Condensed Consolidated Statements of Comprehensive Income </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/CondensedConsolidatedStatementsOfComprehensiveIncome </Role> |
| | | <ShortName> Condensed Consolidated Statements of Comprehensive Income </ShortName> |
| | | <MenuCategory> Statements </MenuCategory> |
| | | <Position> 5 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R6.htm </HtmlFileName> |
| | | <LongName> 1004000 - Statement - Condensed Consolidated Statements of Cash Flows </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/CondensedConsolidatedStatementsOfCashFlows </Role> |
| | | <ShortName> Condensed Consolidated Statements of Cash Flows </ShortName> |
| | | <MenuCategory> Statements </MenuCategory> |
| | | <Position> 6 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R7.htm </HtmlFileName> |
| | | <LongName> 1005000 - Statement - Consolidated Statement of Stockholders' Deficit Statement </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/ConsolidatedStatementOfStockholdersDeficitStatement </Role> |
| | | <ShortName> Consolidated Statement of Stockholders' Deficit Statement </ShortName> |
| | | <MenuCategory> Statements </MenuCategory> |
| | | <Position> 7 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R8.htm </HtmlFileName> |
| | | <LongName> 2101100 - Disclosure - Nature of Business and Basis of Presentation </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/NatureOfBusinessAndBasisOfPresentation </Role> |
| | | <ShortName> Nature of Business and Basis of Presentation </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 8 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R9.htm </HtmlFileName> |
| | | <LongName> 2102100 - Disclosure - Summary of Significant Accounting Policies and Recently Issued Accounting Standards </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SummaryOfSignificantAccountingPoliciesAndRecentlyIssuedAccountingStandards </Role> |
| | | <ShortName> Summary of Significant Accounting Policies and Recently Issued Accounting Standards </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 9 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R10.htm </HtmlFileName> |
| | | <LongName> 2103100 - Disclosure - Supplemental Financial Information </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SupplementalFinancialInformation </Role> |
| | | <ShortName> Supplemental Financial Information </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 10 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R11.htm </HtmlFileName> |
| | | <LongName> 2104100 - Disclosure - Debt </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/Debt </Role> |
| | | <ShortName> Debt </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 11 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R12.htm </HtmlFileName> |
| | | <LongName> 2105100 - Disclosure - Income Taxes </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/IncomeTaxes </Role> |
| | | <ShortName> Income Taxes </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 12 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R13.htm </HtmlFileName> |
| | | <LongName> 2106100 - Disclosure - Guarantees, Commitments and Contingencies </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/GuaranteesCommitmentsAndContingencies </Role> |
| | | <ShortName> Guarantees, Commitments and Contingencies </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 13 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R14.htm </HtmlFileName> |
| | | <LongName> 2107100 - Disclosure - Segment Information </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SegmentInformation </Role> |
| | | <ShortName> Segment Information </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 14 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R15.htm </HtmlFileName> |
| | | <LongName> 2108100 - Disclosure - Revenue </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/Revenue </Role> |
| | | <ShortName> Revenue </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 15 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R16.htm </HtmlFileName> |
| | | <LongName> 2109100 - Disclosure - Earnings Per Share </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/EarningsPerShare </Role> |
| | | <ShortName> Earnings Per Share </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 16 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R17.htm </HtmlFileName> |
| | | <LongName> 2110100 - Disclosure - Accumulated Other Comprehensive Loss </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/AccumulatedOtherComprehensiveLoss </Role> |
| | | <ShortName> Accumulated Other Comprehensive Loss </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 17 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R18.htm </HtmlFileName> |
| | | <LongName> 2111100 - Disclosure - Subsequent Event </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SubsequentEvent </Role> |
| | | <ShortName> Subsequent Event </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 18 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R19.htm </HtmlFileName> |
| | | <LongName> 2201201 - Disclosure - Nature of Business and Basis of Presentation (Policies) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/NatureOfBusinessAndBasisOfPresentationPolicies </Role> |
| | | <ShortName> Nature of Business and Basis of Presentation (Policies) </ShortName> |
| | | <MenuCategory> Policies </MenuCategory> |
| | | <ParentRole> http://www.blue-bird.com/role/SummaryOfSignificantAccountingPoliciesAndRecentlyIssuedAccountingStandards </ParentRole> |
| | | <Position> 19 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R20.htm </HtmlFileName> |
| | | <LongName> 2303301 - Disclosure - Supplemental Financial Information (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SupplementalFinancialInformationTables </Role> |
| | | <ShortName> Supplemental Financial Information (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.blue-bird.com/role/SupplementalFinancialInformation </ParentRole> |
| | | <Position> 20 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R21.htm </HtmlFileName> |
| | | <LongName> 2304301 - Disclosure - Debt (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/DebtTables </Role> |
| | | <ShortName> Debt (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.blue-bird.com/role/Debt </ParentRole> |
| | | <Position> 21 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R22.htm </HtmlFileName> |
| | | <LongName> 2307301 - Disclosure - Segment Information (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SegmentInformationTables </Role> |
| | | <ShortName> Segment Information (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.blue-bird.com/role/SegmentInformation </ParentRole> |
| | | <Position> 22 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R23.htm </HtmlFileName> |
| | | <LongName> 2308301 - Disclosure - Revenue (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/RevenueTables </Role> |
| | | <ShortName> Revenue (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.blue-bird.com/role/Revenue </ParentRole> |
| | | <Position> 23 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R24.htm </HtmlFileName> |
| | | <LongName> 2309301 - Disclosure - Earnings Per Share (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/EarningsPerShareTables </Role> |
| | | <ShortName> Earnings Per Share (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.blue-bird.com/role/EarningsPerShare </ParentRole> |
| | | <Position> 24 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R25.htm </HtmlFileName> |
| | | <LongName> 2310301 - Disclosure - Accumulated Other Comprehensive Loss (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/AccumulatedOtherComprehensiveLossTables </Role> |
| | | <ShortName> Accumulated Other Comprehensive Loss (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.blue-bird.com/role/AccumulatedOtherComprehensiveLoss </ParentRole> |
| | | <Position> 25 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R26.htm </HtmlFileName> |
| | | <LongName> 2402401 - Disclosure - Summary of Significant Accounting Policies and Recently Issued Accounting Standards Significant Accounting Policies - Narrative (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SummaryOfSignificantAccountingPoliciesAndRecentlyIssuedAccountingStandardsSignificantAccountingPoliciesNarrativeDetails </Role> |
| | | <ShortName> Summary of Significant Accounting Policies and Recently Issued Accounting Standards Significant Accounting Policies - Narrative (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 26 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R27.htm </HtmlFileName> |
| | | <LongName> 2403402 - Disclosure - Supplemental Financial Information - Inventories (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SupplementalFinancialInformationInventoriesDetails </Role> |
| | | <ShortName> Supplemental Financial Information - Inventories (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 27 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R28.htm </HtmlFileName> |
| | | <LongName> 2403403 - Disclosure - Supplemental Financial Information - Product Warranty Rollforward (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SupplementalFinancialInformationProductWarrantyRollforwardDetails </Role> |
| | | <ShortName> Supplemental Financial Information - Product Warranty Rollforward (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 28 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R29.htm </HtmlFileName> |
| | | <LongName> 2403404 - Disclosure - Supplemental Financial Information - Extended Warranty Income (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SupplementalFinancialInformationExtendedWarrantyIncomeDetails </Role> |
| | | <ShortName> Supplemental Financial Information - Extended Warranty Income (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 29 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R30.htm </HtmlFileName> |
| | | <LongName> 2403405 - Disclosure - Supplemental Financial Information Remaining Performance Obligation (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SupplementalFinancialInformationRemainingPerformanceObligationDetails </Role> |
| | | <ShortName> Supplemental Financial Information Remaining Performance Obligation (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 30 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R31.htm </HtmlFileName> |
| | | <LongName> 2403406 - Disclosure - Supplemental Financial Information - Self Insurance (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SupplementalFinancialInformationSelfInsuranceDetails </Role> |
| | | <ShortName> Supplemental Financial Information - Self Insurance (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 31 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R32.htm </HtmlFileName> |
| | | <LongName> 2403407 - Disclosure - Supplemental Financial Information - Narrative (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SupplementalFinancialInformationNarrativeDetails </Role> |
| | | <ShortName> Supplemental Financial Information - Narrative (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 32 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R33.htm </HtmlFileName> |
| | | <LongName> 2403408 - Disclosure - Supplemental Financial Information - Pension Expense (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SupplementalFinancialInformationPensionExpenseDetails </Role> |
| | | <ShortName> Supplemental Financial Information - Pension Expense (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 33 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R34.htm </HtmlFileName> |
| | | <LongName> 2403409 - Disclosure - Supplemental Financial Information Supplemental Financial Information - Derivative Instruments (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SupplementalFinancialInformationSupplementalFinancialInformationDerivativeInstrumentsDetails </Role> |
| | | <ShortName> Supplemental Financial Information Supplemental Financial Information - Derivative Instruments (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 34 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R35.htm </HtmlFileName> |
| | | <LongName> 2403410 - Disclosure - Supplemental Financial Information Supplemental Financial Information - Equity Investment in Affiliate (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SupplementalFinancialInformationSupplementalFinancialInformationEquityInvestmentInAffiliateDetails </Role> |
| | | <ShortName> Supplemental Financial Information Supplemental Financial Information - Equity Investment in Affiliate (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 35 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R36.htm </HtmlFileName> |
| | | <LongName> 2403411 - Disclosure - Supplemental Financial Information Supplemental Financial Information - Summarized Financial Information (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SupplementalFinancialInformationSupplementalFinancialInformationSummarizedFinancialInformationDetails </Role> |
| | | <ShortName> Supplemental Financial Information Supplemental Financial Information - Summarized Financial Information (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 36 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R37.htm </HtmlFileName> |
| | | <LongName> 2404402 - Disclosure - Debt - Narrative (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/DebtNarrativeDetails </Role> |
| | | <ShortName> Debt - Narrative (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 37 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R38.htm </HtmlFileName> |
| | | <LongName> 2404404 - Disclosure - Debt - Schedule of Long-term Debt (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/DebtScheduleOfLongTermDebtDetails </Role> |
| | | <ShortName> Debt - Schedule of Long-term Debt (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 38 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R39.htm </HtmlFileName> |
| | | <LongName> 2404405 - Disclosure - Debt - Maturity Schedule (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/DebtMaturityScheduleDetails </Role> |
| | | <ShortName> Debt - Maturity Schedule (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 39 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R40.htm </HtmlFileName> |
| | | <LongName> 2405401 - Disclosure - Income Taxes (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/IncomeTaxesDetails </Role> |
| | | <ShortName> Income Taxes (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.blue-bird.com/role/IncomeTaxes </ParentRole> |
| | | <Position> 40 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R41.htm </HtmlFileName> |
| | | <LongName> 2406401 - Disclosure - Guarantees, Commitments and Contingencies Gaurantees, Commitments and Contingencies - Narrative (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/GuaranteesCommitmentsAndContingenciesGauranteesCommitmentsAndContingenciesNarrativeDetails </Role> |
| | | <ShortName> Guarantees, Commitments and Contingencies Gaurantees, Commitments and Contingencies - Narrative (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 41 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R42.htm </HtmlFileName> |
| | | <LongName> 2407402 - Disclosure - Segment Information (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SegmentInformationDetails </Role> |
| | | <ShortName> Segment Information (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.blue-bird.com/role/SegmentInformationTables </ParentRole> |
| | | <Position> 42 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R43.htm </HtmlFileName> |
| | | <LongName> 2407403 - Disclosure - Segment Information - Reconciliation of Segment Gross Profit (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SegmentInformationReconciliationOfSegmentGrossProfitDetails </Role> |
| | | <ShortName> Segment Information - Reconciliation of Segment Gross Profit (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 43 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R44.htm </HtmlFileName> |
| | | <LongName> 2408402 - Disclosure - Revenue (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/RevenueDetails </Role> |
| | | <ShortName> Revenue (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.blue-bird.com/role/RevenueTables </ParentRole> |
| | | <Position> 44 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R45.htm </HtmlFileName> |
| | | <LongName> 2409402 - Disclosure - Earnings Per Share - Summary of Basic and Diluted Earnings Per Share (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/EarningsPerShareSummaryOfBasicAndDilutedEarningsPerShareDetails </Role> |
| | | <ShortName> Earnings Per Share - Summary of Basic and Diluted Earnings Per Share (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 45 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R46.htm </HtmlFileName> |
| | | <LongName> 2409403 - Disclosure - Earnings Per Share - Narrative (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/EarningsPerShareNarrativeDetails </Role> |
| | | <ShortName> Earnings Per Share - Narrative (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 46 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R47.htm </HtmlFileName> |
| | | <LongName> 2410402 - Disclosure - Accumulated Other Comprehensive Loss (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/AccumulatedOtherComprehensiveLossDetails </Role> |
| | | <ShortName> Accumulated Other Comprehensive Loss (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.blue-bird.com/role/AccumulatedOtherComprehensiveLossTables </ParentRole> |
| | | <Position> 47 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R48.htm </HtmlFileName> |
| | | <LongName> 2411401 - Disclosure - Subsequent Event (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.blue-bird.com/role/SubsequentEventDetails </Role> |
| | | <ShortName> Subsequent Event (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.blue-bird.com/role/SubsequentEvent </ParentRole> |
| | | <Position> 48 </Position> |
| | | </Report> |
| | <Report instance="a10-q20203q070420.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R9999.htm </HtmlFileName> |
| | | <LongName> Uncategorized Items - a10-q20203q070420.htm </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://xbrl.sec.gov/role/uncategorizedFacts </Role> |
| | | <ShortName> Uncategorized Items - a10-q20203q070420.htm </ShortName> |
| | | <MenuCategory> Cover </MenuCategory> |
| | | <Position> 49 </Position> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <LongName> All Reports </LongName> |
| | | <ReportType> Book </ReportType> |
| | | <ShortName> All Reports </ShortName> |
| | | </Report> |
| | </MyReports> |
| <InputFiles> |
| | <File doctype="10-Q" original="a10-q20203q070420.htm"> a10-q20203q070420.htm </File> |
| | <File> a10q2020q3ex101.htm </File> |
| | <File> a10q2020q3ex102.htm </File> |
| | <File> a10q2020q3ex103.htm </File> |
| | <File> a10q2020q3ex311.htm </File> |
| | <File> a10q2020q3ex312.htm </File> |
| | <File> a10q2020q3ex321.htm </File> |
| | <File> a10q2020q4ex104.htm </File> |
| | <File> blbd-20200704.xsd </File> |
| | <File> blbd-20200704_cal.xml </File> |
| | <File> blbd-20200704_def.xml </File> |
| | <File> blbd-20200704_lab.xml </File> |
| | <File> blbd-20200704_pre.xml </File> |
| | </InputFiles> |
| <SupplementalFiles/> |
| <BaseTaxonomies> |
| | <BaseTaxonomy> http://fasb.org/srt/2020-01-31 </BaseTaxonomy> |
| | <BaseTaxonomy> http://xbrl.sec.gov/dei/2019-01-31 </BaseTaxonomy> |
| | <BaseTaxonomy> http://xbrl.sec.gov/country/2020-01-31 </BaseTaxonomy> |
| | <BaseTaxonomy> http://fasb.org/us-gaap/2020-01-31 </BaseTaxonomy> |
| | </BaseTaxonomies> |
| <HasPresentationLinkbase> true </HasPresentationLinkbase> |
| <HasCalculationLinkbase> true </HasCalculationLinkbase> |
| </FilingSummary> |