3.24.3 html 298 346 1 false 89 0 false 7 false false R1.htm 0000001 - Document - Cover Sheet http://www.atlantic-international.com/role/Cover Cover Cover 1 false false R2.htm 9952151 - Statement - Condensed Consolidated Balance Sheets (Unaudited) Sheet http://www.atlantic-international.com/role/CondensedConsolidatedBalanceSheetsUnaudited Condensed Consolidated Balance Sheets (Unaudited) Statements 2 false false R3.htm 9952152 - Statement - Condensed Consolidated Balance Sheets (Unaudited) (Parentheticals) Sheet http://www.atlantic-international.com/role/CondensedConsolidatedBalanceSheetsUnauditedParentheticals Condensed Consolidated Balance Sheets (Unaudited) (Parentheticals) Statements 3 false false R4.htm 9952153 - Statement - Condensed Consolidated Statements of Operations (Unaudited) Sheet http://www.atlantic-international.com/role/CondensedConsolidatedStatementsofOperationsUnaudited Condensed Consolidated Statements of Operations (Unaudited) Statements 4 false false R5.htm 9952154 - Statement - Condensed Consolidated Statements of Changes in Stockholders??? Equity (Deficit) Sheet http://www.atlantic-international.com/role/CondensedConsolidatedStatementsofChangesinStockholdersEquityDeficit Condensed Consolidated Statements of Changes in Stockholders??? Equity (Deficit) Statements 5 false false R6.htm 9952155 - Statement - Condensed Consolidated Statements of Cash Flows (Unaudited) Sheet http://www.atlantic-international.com/role/CondensedConsolidatedStatementsofCashFlowsUnaudited Condensed Consolidated Statements of Cash Flows (Unaudited) Statements 6 false false R7.htm 9952156 - Disclosure - Organization and Nature of Operations Sheet http://www.atlantic-international.com/role/OrganizationandNatureofOperations Organization and Nature of Operations Notes 7 false false R8.htm 9952157 - Disclosure - Merger Sheet http://www.atlantic-international.com/role/Merger Merger Notes 8 false false R9.htm 9952158 - Disclosure - Summary of Significant Accounting Policies Sheet http://www.atlantic-international.com/role/SummaryofSignificantAccountingPolicies Summary of Significant Accounting Policies Notes 9 false false R10.htm 9952159 - Disclosure - Revenue Recognition and Accounts Receivable Sheet http://www.atlantic-international.com/role/RevenueRecognitionandAccountsReceivable Revenue Recognition and Accounts Receivable Notes 10 false false R11.htm 9952160 - Disclosure - Property and Equipment Sheet http://www.atlantic-international.com/role/PropertyandEquipment Property and Equipment Notes 11 false false R12.htm 9952161 - Disclosure - Intangible Assets Sheet http://www.atlantic-international.com/role/IntangibleAssets Intangible Assets Notes 12 false false R13.htm 9952162 - Disclosure - Leases Sheet http://www.atlantic-international.com/role/Leases Leases Notes 13 false false R14.htm 9952163 - Disclosure - Debt Sheet http://www.atlantic-international.com/role/Debt Debt Notes 14 false false R15.htm 9952164 - Disclosure - Accrued Expenses and Other Current Liabilities Sheet http://www.atlantic-international.com/role/AccruedExpensesandOtherCurrentLiabilities Accrued Expenses and Other Current Liabilities Notes 15 false false R16.htm 9952165 - Disclosure - Commitments and Contingencies Sheet http://www.atlantic-international.com/role/CommitmentsandContingencies Commitments and Contingencies Notes 16 false false R17.htm 9952166 - Disclosure - Fair Value Measurements Sheet http://www.atlantic-international.com/role/FairValueMeasurements Fair Value Measurements Notes 17 false false R18.htm 9952167 - Disclosure - Concentrations of Credit Risk Sheet http://www.atlantic-international.com/role/ConcentrationsofCreditRisk Concentrations of Credit Risk Notes 18 false false R19.htm 9952168 - Disclosure - Members??? Capital and Mezzanine Capital Sheet http://www.atlantic-international.com/role/MembersCapitalandMezzanineCapital Members??? Capital and Mezzanine Capital Notes 19 false false R20.htm 9952169 - Disclosure - Related Party Transactions Sheet http://www.atlantic-international.com/role/RelatedPartyTransactions Related Party Transactions Notes 20 false false R21.htm 9952170 - Disclosure - Stock-Based Compensation Sheet http://www.atlantic-international.com/role/StockBasedCompensation Stock-Based Compensation Notes 21 false false R22.htm 9952171 - Disclosure - Income Taxes Sheet http://www.atlantic-international.com/role/IncomeTaxes Income Taxes Notes 22 false false R23.htm 9952172 - Disclosure - Earnings Per Share Sheet http://www.atlantic-international.com/role/EarningsPerShare Earnings Per Share Notes 23 false false R24.htm 9952173 - Disclosure - Subsequent Events Sheet http://www.atlantic-international.com/role/SubsequentEvents Subsequent Events Notes 24 false false R25.htm 995410 - Disclosure - Pay vs Performance Disclosure Sheet http://xbrl.sec.gov/ecd/role/PvpDisclosure Pay vs Performance Disclosure Notes 25 false false R26.htm 995445 - Disclosure - Insider Trading Arrangements Sheet http://xbrl.sec.gov/ecd/role/InsiderTradingArrangements Insider Trading Arrangements Notes 26 false false R27.htm 9954471 - Disclosure - Summary of Significant Accounting Policies (Policies) Sheet http://www.atlantic-international.com/role/SummaryofSignificantAccountingPoliciesPolicies Summary of Significant Accounting Policies (Policies) Policies http://www.atlantic-international.com/role/SummaryofSignificantAccountingPolicies 27 false false R28.htm 9954472 - Disclosure - Revenue Recognition and Accounts Receivable (Tables) Sheet http://www.atlantic-international.com/role/RevenueRecognitionandAccountsReceivableTables Revenue Recognition and Accounts Receivable (Tables) Tables http://www.atlantic-international.com/role/RevenueRecognitionandAccountsReceivable 28 false false R29.htm 9954473 - Disclosure - Property and Equipment (Tables) Sheet http://www.atlantic-international.com/role/PropertyandEquipmentTables Property and Equipment (Tables) Tables http://www.atlantic-international.com/role/PropertyandEquipment 29 false false R30.htm 9954474 - Disclosure - Intangible Assets (Tables) Sheet http://www.atlantic-international.com/role/IntangibleAssetsTables Intangible Assets (Tables) Tables http://www.atlantic-international.com/role/IntangibleAssets 30 false false R31.htm 9954475 - Disclosure - Leases (Tables) Sheet http://www.atlantic-international.com/role/LeasesTables Leases (Tables) Tables http://www.atlantic-international.com/role/Leases 31 false false R32.htm 9954476 - Disclosure - Debt (Tables) Sheet http://www.atlantic-international.com/role/DebtTables Debt (Tables) Tables http://www.atlantic-international.com/role/Debt 32 false false R33.htm 9954477 - Disclosure - Accrued Expenses and Other Current Liabilities (Tables) Sheet http://www.atlantic-international.com/role/AccruedExpensesandOtherCurrentLiabilitiesTables Accrued Expenses and Other Current Liabilities (Tables) Tables http://www.atlantic-international.com/role/AccruedExpensesandOtherCurrentLiabilities 33 false false R34.htm 9954478 - Disclosure - Fair Value Measurements (Tables) Sheet http://www.atlantic-international.com/role/FairValueMeasurementsTables Fair Value Measurements (Tables) Tables http://www.atlantic-international.com/role/FairValueMeasurements 34 false false R35.htm 9954479 - Disclosure - Stock-Based Compensation (Tables) Sheet http://www.atlantic-international.com/role/StockBasedCompensationTables Stock-Based Compensation (Tables) Tables http://www.atlantic-international.com/role/StockBasedCompensation 35 false false R36.htm 9954480 - Disclosure - Earnings Per Share (Tables) Sheet http://www.atlantic-international.com/role/EarningsPerShareTables Earnings Per Share (Tables) Tables http://www.atlantic-international.com/role/EarningsPerShare 36 false false R37.htm 9954481 - Disclosure - Organization and Nature of Operations (Details) Sheet http://www.atlantic-international.com/role/OrganizationandNatureofOperationsDetails Organization and Nature of Operations (Details) Details http://www.atlantic-international.com/role/OrganizationandNatureofOperations 37 false false R38.htm 9954482 - Disclosure - Merger (Details) Sheet http://www.atlantic-international.com/role/MergerDetails Merger (Details) Details http://www.atlantic-international.com/role/Merger 38 false false R39.htm 9954483 - Disclosure - Summary of Significant Accounting Policies (Details) Sheet http://www.atlantic-international.com/role/SummaryofSignificantAccountingPoliciesDetails Summary of Significant Accounting Policies (Details) Details http://www.atlantic-international.com/role/SummaryofSignificantAccountingPoliciesPolicies 39 false false R40.htm 9954484 - Disclosure - Revenue Recognition and Accounts Receivable - Schedule of Disaggregated Revenues (Details) Sheet http://www.atlantic-international.com/role/RevenueRecognitionandAccountsReceivableScheduleofDisaggregatedRevenuesDetails Revenue Recognition and Accounts Receivable - Schedule of Disaggregated Revenues (Details) Details 40 false false R41.htm 9954485 - Disclosure - Revenue Recognition and Accounts Receivable - Narrative (Details) Sheet http://www.atlantic-international.com/role/RevenueRecognitionandAccountsReceivableNarrativeDetails Revenue Recognition and Accounts Receivable - Narrative (Details) Details 41 false false R42.htm 9954486 - Disclosure - Revenue Recognition and Accounts Receivable - Schedule of Accounts Receivable (Details) Sheet http://www.atlantic-international.com/role/RevenueRecognitionandAccountsReceivableScheduleofAccountsReceivableDetails Revenue Recognition and Accounts Receivable - Schedule of Accounts Receivable (Details) Details 42 false false R43.htm 9954487 - Disclosure - Property and Equipment - Schedule of Property and Equipment (Details) Sheet http://www.atlantic-international.com/role/PropertyandEquipmentScheduleofPropertyandEquipmentDetails Property and Equipment - Schedule of Property and Equipment (Details) Details 43 false false R44.htm 9954488 - Disclosure - Property and Equipment (Details) Sheet http://www.atlantic-international.com/role/PropertyandEquipmentDetails Property and Equipment (Details) Details http://www.atlantic-international.com/role/PropertyandEquipmentTables 44 false false R45.htm 9954489 - Disclosure - Intangible Assets - Schedule of Intangible Assets (Details) Sheet http://www.atlantic-international.com/role/IntangibleAssetsScheduleofIntangibleAssetsDetails Intangible Assets - Schedule of Intangible Assets (Details) Details 45 false false R46.htm 9954490 - Disclosure - Intangible Assets (Details) Sheet http://www.atlantic-international.com/role/IntangibleAssetsDetails Intangible Assets (Details) Details http://www.atlantic-international.com/role/IntangibleAssetsTables 46 false false R47.htm 9954491 - Disclosure - Leases (Details) Sheet http://www.atlantic-international.com/role/LeasesDetails Leases (Details) Details http://www.atlantic-international.com/role/LeasesTables 47 false false R48.htm 9954492 - Disclosure - Leases - Schedule of Weighted Average Remaining Lease Term and Discount Rate for Operating Leases (Details) Sheet http://www.atlantic-international.com/role/LeasesScheduleofWeightedAverageRemainingLeaseTermandDiscountRateforOperatingLeasesDetails Leases - Schedule of Weighted Average Remaining Lease Term and Discount Rate for Operating Leases (Details) Details 48 false false R49.htm 9954493 - Disclosure - Leases - Schedule of Future Minimum Payments for Operating Leases (Details) Sheet http://www.atlantic-international.com/role/LeasesScheduleofFutureMinimumPaymentsforOperatingLeasesDetails Leases - Schedule of Future Minimum Payments for Operating Leases (Details) Details 49 false false R50.htm 9954494 - Disclosure - Debt - Schedule of Debt Breakdown (Details) Sheet http://www.atlantic-international.com/role/DebtScheduleofDebtBreakdownDetails Debt - Schedule of Debt Breakdown (Details) Details 50 false false R51.htm 9954495 - Disclosure - Debt - Revolver (Details) Sheet http://www.atlantic-international.com/role/DebtRevolverDetails Debt - Revolver (Details) Details 51 false false R52.htm 9954496 - Disclosure - Debt - Schedule of Borrowings Under Revolver (Details) Sheet http://www.atlantic-international.com/role/DebtScheduleofBorrowingsUnderRevolverDetails Debt - Schedule of Borrowings Under Revolver (Details) Details 52 false false R53.htm 9954497 - Disclosure - Debt - Term Notes (Details) Notes http://www.atlantic-international.com/role/DebtTermNotesDetails Debt - Term Notes (Details) Details 53 false false R54.htm 9954498 - Disclosure - Debt - Seller Notes (Details) Notes http://www.atlantic-international.com/role/DebtSellerNotesDetails Debt - Seller Notes (Details) Details 54 false false R55.htm 9954499 - Disclosure - Debt - Earnout Notes (Details) Notes http://www.atlantic-international.com/role/DebtEarnoutNotesDetails Debt - Earnout Notes (Details) Details 55 false false R56.htm 9954500 - Disclosure - Debt - 2023 and 2024 Amendments to Seller and Earnout Notes (Details) Notes http://www.atlantic-international.com/role/Debt2023and2024AmendmentstoSellerandEarnoutNotesDetails Debt - 2023 and 2024 Amendments to Seller and Earnout Notes (Details) Details 56 false false R57.htm 9954501 - Disclosure - Debt - Credit Agreement (Details) Sheet http://www.atlantic-international.com/role/DebtCreditAgreementDetails Debt - Credit Agreement (Details) Details 57 false false R58.htm 9954502 - Disclosure - Debt - Promissory Note (Details) Sheet http://www.atlantic-international.com/role/DebtPromissoryNoteDetails Debt - Promissory Note (Details) Details 58 false false R59.htm 9954503 - Disclosure - Debt - Merger Note (Details) Sheet http://www.atlantic-international.com/role/DebtMergerNoteDetails Debt - Merger Note (Details) Details 59 false false R60.htm 9954504 - Disclosure - Debt - Schedule of Future Minimum Principal Payments on Company???s Outstanding Debt (Details) Sheet http://www.atlantic-international.com/role/DebtScheduleofFutureMinimumPrincipalPaymentsonCompanysOutstandingDebtDetails Debt - Schedule of Future Minimum Principal Payments on Company???s Outstanding Debt (Details) Details 60 false false R61.htm 9954505 - Disclosure - Debt - Interest Expense (Details) Sheet http://www.atlantic-international.com/role/DebtInterestExpenseDetails Debt - Interest Expense (Details) Details 61 false false R62.htm 9954506 - Disclosure - Accrued Expenses and Other Current Liabilities (Details) - Schedule of Accrued Expenses and Other Current Liabilities Sheet http://www.atlantic-international.com/role/AccruedExpensesandOtherCurrentLiabilitiesDetailsScheduleofAccruedExpensesandOtherCurrentLiabilities Accrued Expenses and Other Current Liabilities (Details) - Schedule of Accrued Expenses and Other Current Liabilities Details http://www.atlantic-international.com/role/AccruedExpensesandOtherCurrentLiabilitiesTables 62 false false R63.htm 9954507 - Disclosure - Commitments and Contingencies - Additional Information (Details) Sheet http://www.atlantic-international.com/role/CommitmentsandContingenciesAdditionalInformationDetails Commitments and Contingencies - Additional Information (Details) Details 63 false false R64.htm 9954508 - Disclosure - Commitments and Contingencies - Consulting Agreement with Robert Machinist (Details) Sheet http://www.atlantic-international.com/role/CommitmentsandContingenciesConsultingAgreementwithRobertMachinistDetails Commitments and Contingencies - Consulting Agreement with Robert Machinist (Details) Details 64 false false R65.htm 9954509 - Disclosure - Commitments and Contingencies - Employment Agreement with Jeffrey Jagid (Details) Sheet http://www.atlantic-international.com/role/CommitmentsandContingenciesEmploymentAgreementwithJeffreyJagidDetails Commitments and Contingencies - Employment Agreement with Jeffrey Jagid (Details) Details 65 false false R66.htm 9954510 - Disclosure - Commitments and Contingencies - Employment Agreement with Christopher Broderick (Details) Sheet http://www.atlantic-international.com/role/CommitmentsandContingenciesEmploymentAgreementwithChristopherBroderickDetails Commitments and Contingencies - Employment Agreement with Christopher Broderick (Details) Details 66 false false R67.htm 9954511 - Disclosure - Commitments and Contingencies - Employment Agreement with Michael Tenore (Details) Sheet http://www.atlantic-international.com/role/CommitmentsandContingenciesEmploymentAgreementwithMichaelTenoreDetails Commitments and Contingencies - Employment Agreement with Michael Tenore (Details) Details 67 false false R68.htm 9954512 - Disclosure - Commitments and Contingencies - Employment Agreement with Todd McNulty (Details) Sheet http://www.atlantic-international.com/role/CommitmentsandContingenciesEmploymentAgreementwithToddMcNultyDetails Commitments and Contingencies - Employment Agreement with Todd McNulty (Details) Details 68 false false R69.htm 9954513 - Disclosure - Fair Value Measurements (Details) Sheet http://www.atlantic-international.com/role/FairValueMeasurementsDetails Fair Value Measurements (Details) Details http://www.atlantic-international.com/role/FairValueMeasurementsTables 69 false false R70.htm 9954514 - Disclosure - Concentrations of Credit Risk (Details) Sheet http://www.atlantic-international.com/role/ConcentrationsofCreditRiskDetails Concentrations of Credit Risk (Details) Details http://www.atlantic-international.com/role/ConcentrationsofCreditRisk 70 false false R71.htm 9954515 - Disclosure - Members??? Capital and Mezzanine Capital (Details) Sheet http://www.atlantic-international.com/role/MembersCapitalandMezzanineCapitalDetails Members??? Capital and Mezzanine Capital (Details) Details http://www.atlantic-international.com/role/MembersCapitalandMezzanineCapital 71 false false R72.htm 9954516 - Disclosure - Related Party Transactions - Transactions with Lyneer Management Holdings (Details) Sheet http://www.atlantic-international.com/role/RelatedPartyTransactionsTransactionswithLyneerManagementHoldingsDetails Related Party Transactions - Transactions with Lyneer Management Holdings (Details) Details 72 false false R73.htm 9954517 - Disclosure - Related Party Transactions- Transactions with IDC (Details) Sheet http://www.atlantic-international.com/role/RelatedPartyTransactionsTransactionswithIDCDetails Related Party Transactions- Transactions with IDC (Details) Details 73 false false R74.htm 9954518 - Disclosure - Related Party Transactions (Details) Sheet http://www.atlantic-international.com/role/RelatedPartyTransactionsDetails Related Party Transactions (Details) Details http://www.atlantic-international.com/role/RelatedPartyTransactions 74 false false R75.htm 9954519 - Disclosure - Stock-Based Compensation - Narrative (Details) Sheet http://www.atlantic-international.com/role/StockBasedCompensationNarrativeDetails Stock-Based Compensation - Narrative (Details) Details 75 false false R76.htm 9954520 - Disclosure - Stock-Based Compensation - Schedule of Restricted Stock Activity (Details) Sheet http://www.atlantic-international.com/role/StockBasedCompensationScheduleofRestrictedStockActivityDetails Stock-Based Compensation - Schedule of Restricted Stock Activity (Details) Details 76 false false R77.htm 9954521 - Disclosure - Stock-Based Compensation - Schedule of Stock-Based Compensation Expense (Details) Sheet http://www.atlantic-international.com/role/StockBasedCompensationScheduleofStockBasedCompensationExpenseDetails Stock-Based Compensation - Schedule of Stock-Based Compensation Expense (Details) Details 77 false false R78.htm 9954522 - Disclosure - Income Taxes (Details) Sheet http://www.atlantic-international.com/role/IncomeTaxesDetails Income Taxes (Details) Details http://www.atlantic-international.com/role/IncomeTaxes 78 false false R79.htm 9954523 - Disclosure - Earnings Per Share (Details) - Schedule of Basic and Diluted Net Loss Per Share Sheet http://www.atlantic-international.com/role/EarningsPerShareDetailsScheduleofBasicandDilutedNetLossPerShare Earnings Per Share (Details) - Schedule of Basic and Diluted Net Loss Per Share Details http://www.atlantic-international.com/role/EarningsPerShareTables 79 false false R80.htm 9954524 - Disclosure - Subsequent Events (Details) Sheet http://www.atlantic-international.com/role/SubsequentEventsDetails Subsequent Events (Details) Details http://www.atlantic-international.com/role/SubsequentEvents 80 false false All Reports Book All Reports altn-20240930.htm altn-20240930.xsd altn-20240930_cal.xml altn-20240930_def.xml altn-20240930_lab.xml altn-20240930_pre.xml http://fasb.org/srt/2024 http://fasb.org/us-gaap/2024 http://xbrl.sec.gov/dei/2024 http://xbrl.sec.gov/ecd/2024 true true