Payables and Accruals [Abstract] Accrued Liabilities Accounts Payable and Accrued Liabilities Disclosure [Text Block] Related Party Transactions [Abstract] Schedule of Related Party Transactions, by Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Related Party [Axis] Related Party [Axis] Related Party [Domain] Related Party [Domain] Henry R. Slack Board of Directors Chairman [Member] George R. Brokaw Executive Vice President [Member] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Annual base salary Due to Related Parties, Current Inventory Disclosure [Abstract] Inventory, Current [Table] Inventory, Current [Table] Loss Contingency Nature [Axis] Loss Contingency Nature [Axis] Loss Contingency, Nature [Domain] Loss Contingency, Nature [Domain] Property and Casualty Claims Property And Casualty Claims [Member] Property And Casualty Claims [Member] Crop Claims Crop Claims [Member] Crop Claims [Member] Inventory [Line Items] Inventory [Line Items] Insurance proceeds received Loss Contingency, Damages Awarded, Value Proceeds received from insurance relating to property and casualty damage claims Proceeds Received from Insurance Relating to Property and Casualty Damage Claims Proceeds Received from Insurance Relating to Property and Casualty Damage Claims Proceeds from federal relief grants Proceeds From Federal Relief Grants Proceeds From Federal Relief Grants Subsequent Events [Abstract] Subsequent Event [Table] Subsequent Event [Table] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event Subsequent Event [Member] Subsequent Event [Line Items] Subsequent Event [Line Items] Acres of land purchased Long Lived Assets Acres Of Land Purchased Long Lived Assets Acres Of Land Purchased Like-kind asset purchased Noncash or Part Noncash Acquisition, Fixed Assets Acquired Debt Disclosure [Abstract] Schedule of long-term debt, net of current portion Schedule of Long-term Debt Instruments [Table Text Block] Schedule of lines of credit Schedule of Line of Credit Facilities [Table Text Block] Schedule of future maturities of debt and lines of credit Schedule of Maturities of Long-term Debt [Table Text Block] Schedule of interest costs expensed and capitalized Schedule Of Interest Expense [Table Text Block] Schedule Of Interest Expense [Table Text Block]. Organization, Consolidation and Presentation of Financial Statements [Abstract] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Ownership [Axis] Ownership [Axis] Ownership [Domain] Ownership [Domain] Citree Citree Holdings I, LLC [Member] Citree Holdings I, LLC [Member] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Land Land [Member] Mineral Rights Mining Properties and Mineral Rights [Member] Citrus Groves Citrus Groves [Member] Citrus Groves [Member] Product and Service [Axis] Product and Service [Axis] Product and Service [Domain] Product and Service [Domain] Citrus Citrus Operations [Member] Citrus Operations [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Area of land owned (in acres) Area of Real Estate Property Number of primary classifications Property, Plant and Equipment, Number of Classifications Property, Plant and Equipment, Number of Classifications Number of business segments Number of Operating Segments Payments to acquire property plant and equipment Payments to Acquire Property, Plant, and Equipment Repayments of debt Repayments of Debt Net proceeds from sale of ranch land Proceeds from Sale of Property, Plant, and Equipment Revenue, description of timing Revenue, Performance Obligation, Description of Timing Accounts receivable, net Accounts Receivable, after Allowance for Credit Loss, Current Net loss attributable to subsidiary Net Income (Loss) Attributable to Noncontrolling Interest Ownership interest (as a percent) Noncontrolling Interest, Ownership Percentage by Parent Proceeds from federal relief program Proceeds From Natural Disaster Relief Proceeds From Natural Disaster Relief Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Credit Facility [Axis] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Revolving Credit Facility Revolving Credit Facility [Member] RLOC Metropolitan Life Insurance Company And New England Life Insurance Company Revolving Line Of Credit [Member] Metropolitan Life Insurance Company And New England Life Insurance Company Revolving Line Of Credit [Member] WCLC Working Capital Line Of Credit [Member] Working Capital Line Of Credit [Member] Letter of Credit Letter of Credit [Member] Metlife Term Loan Metlife Term Loan [Member] Metlife Term Loan [Member] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Farm and Ranch Land Farm and Ranch Land [Member] Farm and Ranch Land [Member] Line of Credit Line of Credit [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Met Fixed-Rate Term Loans Fixed Rate Term Loan [Member] Fixed Rate Term Loan [Member] Met Variable-Rate Term Loans Variable Rate Term Loan [Member] Variable Rate Term Loan [Member] Fixed Rate Term Loan1 Fixed Rate Term Loan1 [Member] Fixed Rate Term Loan1 [Member] Fixed Rate Term Loan 2 Fixed Rate Term Loan 2 [Member] Fixed Rate Term Loan 2 [Member] Silver Nip Citrus Debt Silver Nip Citrus Debt [Member] Silver Nip Citrus Debt [Member] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] LIBOR London Interbank Offered Rate (LIBOR) [Member] Statistical Measurement [Axis] Statistical Measurement [Axis] Statistical Measurement [Domain] Statistical Measurement [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Short-term Debt, Type [Axis] Short-term Debt, Type [Axis] Short-term Debt, Type [Domain] Short-term Debt, Type [Domain] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] Silver Nip Citrus Silver Nip Citrus [Member] Silver Nip Citrus [Member] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Citrus Grove Charlotte County Citrus Grove [Member] Charlotte County Citrus Grove [Member] Lender Name [Axis] Lender Name [Axis] Line of Credit Facility, Lender [Domain] Line of Credit Facility, Lender [Domain] Prudential Prudential Mortgage Capital Company, LLC [Member] Prudential Mortgage Capital Company, LLC [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Revolving line of credit Line of Credit Facility, Maximum Borrowing Capacity Area of land (in acres) Debt Instrument Collateral Property Acreage Debt Instrument, Collateral, Property Acreage. Quarterly principal payments Debt Instrument, Periodic Payment, Principal Fixed interest rate Debt Instrument, Interest Rate, Stated Percentage LIBOR spread (as a percent) Debt Instrument, Basis Spread on Variable Rate LIBOR spread subject to adjustment period Debt Instrument, London Interbank Offered Rate (LIBOR) Spread Subject to Adjustment, Period Debt Instrument, London Interbank Offered Rate (LIBOR) Spread Subject to Adjustment, Period Variable interest rate Debt Instrument, Interest Rate, Effective Percentage Prepayment amount of the fixed term loan (up to) Debt Instrument Amount Of Prepayment Without Penalty Debt Instrument Amount Of Prepayment Without Penalty Availability under line of credit Line of Credit Facility, Remaining Borrowing Capacity Borrowings on revolving lines of credit Proceeds from Lines of Credit Annual commitment fee (as a percent) Line of Credit Facility, Commitment Fee Percentage Outstanding balance Long-term Line of Credit Outstanding letters of credit Letters of Credit Outstanding, Amount Debt issuance cost, gross Debt Issuance Costs, Gross Debt issuance cost, net Debt Issuance Costs, Net Minimum debt service coverage ratio Debt Instrument Covenant Minimum Debt Coverage Ratio Debt Instrument, Covenant, Minimum Debt Coverage Ratio. Tangible net worth Debt Instrument Covenant Minimum Tangible Net Worth Debt Instrument, Covenant, Minimum Tangible Net Worth. Percentage of consolidated net income Debt Instrument Covenant, Percentage Annual Increase Debt Instrument Covenant, Percentage Annual Increase Annual increase of tangible net worth Debt Instrument Covenant, Minimum Tangible Net worth, Annual Increase Debt Instrument Covenant, Minimum Tangible Net worth, Annual Increase Minimum current ratio Line of Credit Facility, Covenant Terms, Minimum Current Ratio Line of Credit Facility, Covenant Terms, Minimum Current Ratio Debt to total assets ratio Ratio of Indebtedness to Net Capital Limit on capital expenditures Debt Instrument Covenant Maximum Capital Expenditure Debt Instrument Covenant Maximum Capital Expenditure Area of property that served as collateral (in acres) Debt Instrument, Collateral, Area Of Property Debt Instrument, Collateral, Area Of Property Number of fixed rate term loans Debt Instrument, Number of Instruments Debt Instrument, Number of Instruments Interest rate term loans Long-term Debt Amount of prepayment Debt Instrument, Amount of Prepayment Debt Instrument, Amount of Prepayment Amount of prepayment in excess of total without penalty Debt Instrument Amount Of Prepayment In Excess of Total Without Penalty Debt Instrument Amount Of Prepayment In Excess of Total Without Penalty Premium payment of penalty Debt Instrument, Premium Payment of Penalty Debt Instrument, Premium Payment of Penalty Covenant ratio Line of Credit Facility, Covenant Terms, Current Ratio Line of Credit Facility, Covenant Terms, Current Ratio Income Tax Disclosure [Abstract] Income Tax Contingency [Table] Income Tax Contingency [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] ASC 610-20 Accounting Standards Update 2017-05 [Member] Income Tax Contingency [Line Items] Income Tax Contingency [Line Items] Deferred gain on sale Deferred Tax Assets, Deferred Gain on Sale Leaseback Transaction Retained earnings Retained Earnings (Accumulated Deficit) Discontinued Operations and Disposal Groups [Abstract] Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Disposal Group Classification [Axis] Disposal Group Classification [Axis] Disposal Group Classification [Domain] Disposal Group Classification [Domain] Discontinued Operations, Disposed of by Sale Discontinued Operations, Disposed of by Sale [Member] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Consideration for discontinued operation Disposal Group, Including Discontinued Operation, Consideration Gain (loss) on disposal of discontinued operation Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax Description of Business and Basis of Presentation Basis of Presentation and Significant Accounting Policies [Text Block] Inventories Inventory Disclosure [Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Segments Segment Reporting, Policy [Policy Text Block] Principles of Consolidation Consolidation, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Recent Accounting Pronouncements and Recently Adopted Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Seasonality Seasonality [Policy Text Block] Seasonality [Policy Text Block] Earnings Per Share [Abstract] Net income attributable to Alico, Inc. common stockholders Net Income (Loss) Attributable to Parent Weighted average number of common shares outstanding - basic (in shares) Weighted Average Number of Shares Outstanding, Basic Dilutive effect of equity-based awards (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Weighted average number of common shares outstanding - diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Net income per common shares attributable to Alico, Inc. common stockholders: Net Income Per Common Shares Attributable to Parent [Abstract] Net Income Per Common Shares Attributable to Parent [Abstract] Basic (in dollars per share) Earnings Per Share, Basic Diluted (in dollars per share) Earnings Per Share, Diluted Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Title of Individual [Axis] Title of Individual [Axis] Title of Individual [Domain] Title of Individual [Domain] Officer Officer [Member] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive securities excluded from computation of earnings per share (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Early and Mid-Season Early And Mid-Season [Member] Early And Mid-Season [Member] Valencias Valencias [Member] Valencias [Member] Fresh Fruit Fresh Fruit [Member] Fresh Fruit [Member] Other Other [Member] Other [Member] Land and Other Leasing Land And Other Leasing [Member] Land And Other Leasing [Member] Segments [Axis] Segments [Axis] Segments [Domain] Segments [Domain] Alico Citrus Alico Citrus [Member] Alico Citrus [Member] Water Resources and Other Operations Water Resources And Other Operations [Member] Water Resources And Other Operations [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Total Revenues Revenue from Contract with Customer, Excluding Assessed Tax Earnings Per Common Share Earnings Per Share [Text Block] Property, Plant and Equipment [Abstract] Property and Equipment, Net Property, Plant and Equipment Disclosure [Text Block] 2020 Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year 2021 Lessee, Operating Lease, Liability, Payments, Due Year Two 2022 Lessee, Operating Lease, Liability, Payments, Due Year Three 2023 Lessee, Operating Lease, Liability, Payments, Due Year Four Total noncancelable future lease obligations Lessee, Operating Lease, Liability, Payments, Due Less: Interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Present value of lease obligations Operating Lease, Liability Schedule of disaggregation of revenue Disaggregation of Revenue [Table Text Block] Condensed balance sheet Assets And Liabilities, Lessee [Table Text Block] Assets And Liabilities, Lessee [Table Text Block] Components of lease cost Lease, Cost [Table Text Block] Maturities of our operating lease obligations Lessee, Operating Lease, Liability, Maturity [Table Text Block] Due within one year Long-term Debt, Maturities, Repayments of Principal, Remainder of Fiscal Year Due between one and two years Long-term Debt, Maturities, Repayments of Principal in Year Two Due between two and three years Long-term Debt, Maturities, Repayments of Principal in Year Three Due between three and four years Long-term Debt, Maturities, Repayments of Principal in Year Four Due between four and five years Long-term Debt, Maturities, Repayments of Principal in Year Five Due beyond five years Long-term Debt, Maturities, Repayments of Principal after Year Five Principal Schedule of property and equipment, net Property, Plant and Equipment [Table Text Block] Subsequent Events Subsequent Events [Text Block] Long-Term Debt and Lines of Credit Long-term Debt [Text Block] Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Asset and Derivative Liabilities/Deferred Gain on Sale Derivative Instruments and Hedging Activities Disclosure [Text Block] Weighted-average remaining lease term Operating Lease, Weighted Average Remaining Lease Term Weighted-average discount rate Operating Lease, Weighted Average Discount Rate, Percent Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Long Lived Assets Held-for-sale by Asset Type [Axis] Long Lived Assets Held-for-sale by Asset Type [Axis] Long Lived Assets Held-for-sale, Name [Domain] Long Lived Assets Held-for-sale, Name [Domain] Hendry County Florida Hendry County Sugarcane Property [Member] Hendry County Sugarcane Property [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Acres of land Long Lived Assets Held For Sale Acres Of Land Long Lived Assets Held For Sale, Acres Of Land. Post-closing adjustment period Disposal Group, Post-Closing Adjustment Period Disposal Group, Post-Closing Adjustment Period Realized gain on disposal Disposal Group Not Discontinued Operation Realized Gain (Loss) On Disposal Disposal Group Not Discontinued Operation Realized Gain Loss On Disposal Deferred gain on sale Deferred Gain on Sale of Property Gain on sale of investment in real estate Gains (Losses) on Sales of Investment Real Estate Retained earnings Derivative asset Derivative Asset, Current Other current liabilities Derivative Liability, Current Loss on derivatives Derivative, Gain (Loss) on Derivative, Net Aggregate amount of payments made due to post closing agreement Amount to be deposited into escrow Discontinued Operation, Amount To Be Deposited Into Escrow Following The Satisfaction Of Certain Terms And Conditions Set Forth In Termination Agreement Discontinued Operation, Amount To Be Deposited Into Escrow Following The Satisfaction Of Certain Terms And Conditions Set Forth In Termination Agreement Equity [Abstract] Stockholders' Equity Stockholders' Equity Note Disclosure [Text Block] Statement of Cash Flows [Abstract] Net cash provided by operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Net income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation, depletion and amortization Depreciation, Depletion and Amortization Deferred income tax (benefit) expense Deferred Income Tax Expense (Benefit) Gain on sale of real estate, property and equipment and assets held for sale Gain (Loss) on Disposition of Property Plant Equipment Change in fair value of derivatives Impairment of long-lived assets Impairment of Long-Lived Assets Held-for-use Impairment of right-of-use asset Operating Lease, Impairment Loss Stock-based compensation expense Share-based Payment Arrangement, Noncash Expense Other Other Operating Activities, Cash Flow Statement Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Accounts receivable Increase (Decrease) in Accounts Receivable Inventories Increase (Decrease) in Inventories Prepaid expenses Increase (Decrease) in Prepaid Guaranteed Payments Increase (Decrease) in Prepaid Guaranteed Payments Other assets Increase (Decrease) in Other Operating Assets Accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Income tax payable Increase (Decrease) in Income Taxes Payable Other liabilities Increase (Decrease) in Other Operating Liabilities Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Cash flows from investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Purchases of property and equipment Net proceeds from sale of property and equipment and assets held for sale Change in deposits on purchase of citrus trees Payments For (Proceeds From) Deposits On Purchase Of Productive Assets Payments For (Proceeds From) Deposits On Purchase Of Productive Assets Deposit on purchase of citrus grove Payments For Deposits On Purchase Of Productive Assets Payments For Deposits On Purchase Of Productive Assets Advances on notes receivables, net Proceeds From (Payments To Acquire) Notes Receivable Proceeds From (Payments To Acquire) Notes Receivable Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Cash flows from financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Repayments on revolving lines of credit Repayments of Lines of Credit Principal payments on term loans Repayments of Medium-term Notes Treasury stock purchases Payments for Repurchase of Common Stock Payment on termination of sugarcane agreement Payments For Termination Of Agreement Payments For Termination Of Agreement Dividends paid Payments of Ordinary Dividends, Common Stock Deferred financing costs Payments of Debt Issuance Costs Net cash provided by (used in) financing activities Net Cash Provided by (Used in) Financing Activities Net increase (decrease) in cash and cash equivalents and restricted cash Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Cash and cash equivalents and restricted cash at beginning of the period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash and cash equivalents and restricted cash at end of the period Segment Reporting [Abstract] Number of operating segments Schedule of information by business segment Schedule of Segment Reporting Information, by Segment [Table Text Block] Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Chief Executive Officer Chief Executive Officer [Member] Board of Directors Chairman Chief Financial Officer Chief Financial Officer [Member] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] 2015 Option Grants Two Thousand And Fifteen Plan [Member] Two Thousand And Fifteen Plan [Member] 2020 Option Grants Two Thousand And Twenty Plan [Member] Two Thousand And Twenty Plan [Member] 2019 Option Grants Two Thousand And Nineteen Option Grants [Member] Two Thousand And Nineteen Option Grants [Member] 2018 Option Grants Two Thousand And Eighteen Option Grants [Member] Two Thousand And Eighteen Option Grants [Member] 2016 Option Grants Two Thousand And Sixteen Option Grants [Member] Two Thousand And Sixteen Option Grants [Member] 2019 Modified Option Grants Two Thousand And Nineteen Modified Option Grants [Member] Two Thousand And Nineteen Modified Option Grants [Member] Award Type [Axis] Award Type [Axis] Award Type [Domain] Award Type [Domain] Restricted Stock Restricted Stock [Member] Options Share-based Payment Arrangement, Option [Member] Vesting [Axis] Vesting [Axis] Vesting [Domain] Vesting [Domain] Tranche One Share-based Payment Arrangement, Tranche One [Member] Tranche Two Share-based Payment Arrangement, Tranche Two [Member] Tranche Three Share-based Payment Arrangement, Tranche Three [Member] Tranche Four Share-based Compensation Award, Tranche Four [Member] Share-based Compensation Award, Tranche Four [Member] Class of Stock [Line Items] Class of Stock [Line Items] Number of shares authorized to be repurchased (up to) Stock Repurchase Program, Number of Shares Authorized to be Repurchased Stock compensation expense Share-based Payment Arrangement, Expense Award vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Unrecognized expense Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Unrecognized compensation cost, expected recognition period Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Shares issued (in dollars per share) Shares Issued, Price Per Share Period of consecutive trading days Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Period of Consecutive Trading Days Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Period of Consecutive Trading Days Amount per share (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Amount Per Share Share-based Compensation Arrangement by Share-based Payment Award, Amount Per Share Period following an executive's termination of employment for a number of reasons Related Party Transaction, Period Following An Executive's Termination of Employment for a Number of Reasons Related Party Transaction, Period Following An Executive's Termination of Employment for a Number of Reasons Period following an executive's termination of employment without cause Related Party Transaction, Period Following An Executive's Termination of Employment Without Cause Related Party Transaction, Period Following An Executive's Termination of Employment Without Cause Share price (in dollars per share) Share Price Percentage of options Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Number of awards vesting (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares Shares forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Number of shares expected to vest (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number Of Options Expected To Vest Share-based Compensation Arrangement by Share-based Payment Award, Number Of Options Expected To Vest Award expiration period Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period Grants in period, weighted average (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Shares issued (in shares) Stock Issued During Period, Shares, New Issues Cost of shares Stock Issued During Period, Value, New Issues Assets Held for Sale Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Depreciable properties Depreciable Property Plant and Equipment [Member] Represents the information pertaining to depreciable assets. Citrus trees Citrus Trees [Member] Citrus Trees [Member]. Equipment and other facilities Machinery and Equipment [Member] Buildings and improvements Building and Building Improvements [Member] Land and land improvements Land and Land Improvements [Member] Property and equipment, gross Property, Plant and Equipment, Gross Less: accumulated depreciation and depletion Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property and equipment, net Property, Plant and Equipment, Net Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Cash paid for amounts included in the measurement of lease liabilities: Cash Flow, Lessee [Abstract] Cash Flow, Lessee [Abstract] Operating cash flows from operating leases Operating Lease, Payments Right-of-use assets obtained in exchange for lease obligations: Right-Of-Use Asset Obtained In Exchange For Lease Liability [Abstract] Right-Of-Use Asset Obtained In Exchange For Lease Liability [Abstract] Operating leases Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Right-of-use assets Operating Lease, Right-of-Use Asset Current lease liabilities Operating Lease, Liability, Current Non-current lease liabilities Operating Lease, Liability, Noncurrent Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Shares Treasury Stock, Shares [Abstract] Beginning Balance (in shares) Treasury Stock, Shares Purchased (in shares) Treasury Stock, Shares, Acquired Issued to employees and directors (in shares) Stock Issued During Period, Shares, Treasury Stock Reissued Ending Balance (in shares) Cost Treasury Stock, Value [Abstract] Beginning Balance Treasury Stock, Value Purchased Treasury Stock, Value, Acquired, Cost Method Issued to employees and directors Stock Issued During Period, Value, Treasury Stock Reissued Ending Balance Income Statement [Abstract] Statement [Table] Statement [Table] Alico Citrus Statement [Line Items] Statement [Line Items] Operating revenues: Revenues [Abstract] Total operating revenues Operating expenses: Costs and Expenses [Abstract] Total operating expenses Cost of Revenue Gross profit Gross Profit General and administrative expenses General and Administrative Expense Income from operations Operating Income (Loss) Other income (expense), net: Nonoperating Income (Expense) [Abstract] Interest expense Interest Expense, Debt Gain on sale of real estate, property and equipment and assets held for sale Change in fair value of derivatives Other income (expense) Other Nonoperating Income (Expense) Total other income (expense), net Nonoperating Income (Expense) Income before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Income tax provision Income Tax Expense (Benefit) Net income Net loss (income) attributable to noncontrolling interests Net income attributable to Alico, Inc. common stockholders Per share information attributable to Alico, Inc. common stockholders: Earnings Per Share, Basic and Diluted [Abstract] Earnings per common share: Weighted-average number of common shares outstanding: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Basic (in shares) Diluted (in shares) Cash dividends declared per common share (in dollars per share) Common Stock, Dividends, Per Share, Declared Schedule of inventories Schedule of Inventory, Current [Table Text Block] Statement of Stockholders' Equity [Abstract] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common stock Common Stock [Member] Additional Paid-In Capital Additional Paid-in Capital [Member] Treasury Stock Treasury Stock [Member] Retained Earnings Retained Earnings [Member] Total Alico, Inc. Equity Parent [Member] Noncontrolling Interest Noncontrolling Interest [Member] Directors Director [Member] Executives Beginning balance (in shares) Shares, Issued Beginning balance Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Net income (loss) Dividends Dividends Treasury stock purchases ASC 610-20 adoption Cumulative Effect of New Accounting Principle in Period of Adoption Stock-based compensation Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture Executive forfeiture Shares Issued, Value, Share-based Payment Arrangement, Forfeited Ending balance (in shares) Ending balance Reconciliation of Revenue from Segments to Consolidated [Table] Reconciliation of Revenue from Segments to Consolidated [Table] Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Operating Segments Operating Segments [Member] Other Corporate Assets Corporate, Non-Segment [Member] Other Depreciation, Depletion and Amortization Segment Reconciling Items [Member] Segment Reporting, Revenue Reconciling Item [Line Items] Segment Reporting, Revenue Reconciling Item [Line Items] Revenues: Total revenues Operating expenses: Cost of Revenue [Abstract] Total operating expenses Gross profit: Gross Profit [Abstract] Depreciation, depletion and amortization: Depreciation, Depletion and Amortization [Abstract] Total depreciation, depletion and amortization Assets: Assets [Abstract] Total assets Assets Cover [Abstract] Document Type Document Type Document Quarterly Report Document Quarterly Report Document Period End Date Document Period End Date Document Transition Report Document Transition Report Entity File Number Entity File Number Entity Registrant Name Entity Registrant Name Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Tax Identification Number Entity Tax Identification Number Entity Address, Address Line One Entity Address, Address Line One Entity Address, Address Line Two Entity Address, Address Line Two Entity Address, City or Town Entity Address, City or Town Entity Address, State or Province Entity Address, State or Province Entity Address, Postal Zip Code Entity Address, Postal Zip Code City Area Code City Area Code Local Phone Number Local Phone Number Title of 12(b) Security Title of 12(b) Security Trading Symbol Trading Symbol Security Exchange Name Security Exchange Name Entity Current Reporting Status Entity Current Reporting Status Entity Interactive Data Current Entity Interactive Data Current Entity Filer Category Entity Filer Category Entity Smaller Reporting Company Entity Small Business Entity Emerging Growth Company Entity Emerging Growth Company Entity Shell Company Entity Shell Company Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Amendment Flag Amendment Flag Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Loss Contingencies [Table] Loss Contingencies [Table] Financial Standby Letter of Credit Financial Standby Letter of Credit [Member] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Outstanding standby letters of credit Line of Credit Facility, Current Borrowing Capacity Line of Credit Facility [Table] Line of Credit Facility [Table] RLOC Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] Principal Deferred Financing Costs, Net Remy W. Trafelet Period of consulting services provided (up to) Related Party Transaction, Period Of Consulting Services Provided Related Party Transaction, Period Of Consulting Services Provided Payments for services and covenants Related Party Transaction, Amounts of Transaction Ad valorem taxes Sales and Excise Tax Payable Accrued interest Interest Payable, Current Accrued employee wages and benefits Accrued Salaries, Current Accrued dividends Dividends Payable, Current Accrued contractual obligation associated with sale of real estate Accrued Contractual Obligation, Current Accrued Contractual Obligation, Current Accrued harvest and haul Consulting And Separation Charges, Current Consulting And Separation Charges, Current Consulting and separation charges Accrued Insurance, Current Accrued insurance Accrued Professional Fees, Current Other accrued liabilities Other Accrued Liabilities, Current Total accrued liabilities Accrued Liabilities, Current Operating lease costs Operating Lease, Cost Operating lease right-of-use asset impairment Citrus Blocks Citrus Blocks [Member] Citrus Blocks [Member] West Ranch West Ranch [Member] West Ranch [Member] Asset impairment charges Asset Impairment Charges Amount of collateral and release substituted Long-Lived Assets, Amount of Collateral And Release Substituted By Bank From Restricted Cash Long-Lived Assets, Amount of Collateral And Release Substituted By Bank From Restricted Cash Number of additional purchases Number of Real Estate Properties Acres of land sold Gain (loss) on disposal of discontinued operation Lease rate Finance Lease, Monthly Lease Finance Lease, Monthly Lease Schedule of assets held for sale Disposal Groups, Including Discontinued Operations [Table Text Block] TBCO Trafelet Brokaw & Co., LLC [Member] Trafelet Brokaw & Co., LLC [Member] Expense under shared services agreement Related Party Transaction, Expenses from Transactions with Related Party Related Party Transactions Related Party Transactions Disclosure [Text Block] Statement of Financial Position [Abstract] ASSETS Current assets: Assets, Current [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Inventories Inventory, Net Assets held for sale Assets Held-for-sale, Not Part of Disposal Group, Current Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Total current assets Assets, Current Restricted cash Restricted Cash and Cash Equivalents Property and equipment, net Goodwill Goodwill Other non-current assets Other Assets, Noncurrent Total assets LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities and Equity [Abstract] Current liabilities: Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current Accrued liabilities Long-term debt, current portion Long-term Debt, Current Maturities Deferred retirement obligations Liability, Other Retirement Benefits, Current Liability, Other Retirement Benefits, Current Income taxes payable Accrued Income Taxes, Current Other current liabilities Other Liabilities, Current Total current liabilities Liabilities, Current Long-term debt: Long-term Debt, Excluding Current Maturities [Abstract] Principal amount, net of current portion Other Long-term Debt, Gross, Noncurrent Other Long-term Debt, Gross, Noncurrent Less: deferred financing costs, net Long-term debt less current portion and deferred financing costs, net Other Long-term Debt, Noncurrent Lines of credit Long-term Line of Credit, Noncurrent Deferred income tax liabilities, net Deferred Income Tax Liabilities, Net Other liabilities Other Liabilities, Noncurrent Total liabilities Liabilities Commitments and Contingencies (Note 12) Commitments and Contingencies Stockholders' equity: Stockholders' Equity Attributable to Parent [Abstract] Preferred stock, no par value, 1,000,000 shares authorized; none issued Preferred Stock, Value, Issued Common stock, $1.00 par value, 15,000,000 shares authorized; 8,416,145 shares issued and 7,479,671 and 7,476,513 shares outstanding at March 31, 2020 and September 30, 2019, respectively Common Stock, Value, Issued Additional paid in capital Additional Paid in Capital, Common Stock Treasury stock, at cost, 936,474 and 939,632 shares held at March 31, 2020 and September 30, 2019, respectively Total Alico stockholders' equity Stockholders' Equity Attributable to Parent Noncontrolling interest Stockholders' Equity Attributable to Noncontrolling Interest Total stockholders' equity Total liabilities and stockholders' equity Liabilities and Equity Interest expense Interest capitalized Interest Costs Capitalized Total Interest Costs Incurred Income Taxes Income Tax Disclosure [Text Block] Unharvested fruit crop on the trees Agricultural Related Inventory, Growing Crops Other Other Inventory, Gross Total inventories Schedule of accrued liabilities Schedule of Accrued Liabilities [Table Text Block] Outstanding purchase commitments Purchase Obligation Majority Shareholder Majority Shareholder [Member] Counterparty Name [Axis] Counterparty Name [Axis] Counterparty Name [Domain] Counterparty Name [Domain] 734 Investors 734 Investors [Member] 734 Investors [Member] Distribution of common stock (in shares) Common Stock, Other Shares, Outstanding Discontinued Operations, Held-for-sale Discontinued Operations, Held-for-sale [Member] Disposal Group Name [Axis] Disposal Group Name [Axis] Disposal Group Name [Domain] Disposal Group Name [Domain] East Ranch Parcels On East Ranch [Member] Parcels On East Ranch [Member] Schedule of stock options using valuation assumptions Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Schedule of treasury stock purchases and issuances Schedule Of Treasury Stock Transactions [Table Text Block] Schedule Of Treasury Stock Transactions [Table Text Block]. Met Citree Term Loan Citree Term Loan [Member] Citree Term Loan [Member] Pru Loans A & B Pru Loans A&B [Member] Pru Loans A&B [Member] Pru Loan E Pru Loan E [Member] Pru Loan E [Member] Pru Loan F Pru Loan F [Member] Pru Loan F [Member] Term Loans and PRU Loans Term Loans and PRU Loans [Member] Term Loans and PRU Loans [Member] Less current portion Long-term debt Long-term Debt, Excluding Current Maturities Schedule of basic and diluted earnings per common share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Common stock, par value per share (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, shares authorized (in shares) Common Stock, Shares Authorized Common stock, shares issued (in shares) Common Stock, Shares, Issued Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Treasury stock at cost, shares (in shares) Segment Information Segment Reporting Disclosure [Text Block] 2019 Modified Option Grant Expected Volatility (as a percent) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Expected Term (in years) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Risk Free Rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate