Acres of land related to land liens Acres of Land Related to Land Liens Acres of land related to land liens. Revision of Prior Period [Axis] Revision of Prior Period [Axis] Accumulated Depreciation Finite-Lived Intangible Assets, Accumulated Amortization Statistical Measurement [Domain] Statistical Measurement [Domain] Schedule of Available-for-Sale Securities Debt Securities, Available-for-Sale [Table Text Block] Cost Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Award Timing Predetermined Award Timing Predetermined [Flag] Related Party Transaction [Axis] Related Party Transaction [Axis] Entity File Number Entity File Number Segment Operating Results Segment Reporting Information, Income (Loss) before Income Taxes [Abstract] Additional Paid-In Capital Additional Paid-in Capital [Member] Equity in earnings of unconsolidated joint ventures, net Equity in earnings of unconsolidated joint ventures, net Equity in earnings of unconsolidated joint ventures Income (Loss) from Equity Method Investments Accrued long-term water assets included in current liabilities Accrued Long-term Water Assets Included in Current Liabilities Accrued Long-term Water Assets Included in Current Liabilities Tabular List, Table Tabular List [Table Text Block] Long Lived Assets Held-for-sale by Asset Type [Axis] Long-Lived Asset, Held-for-Sale, Type [Axis] Income tax benefit related to other comprehensive loss items Other Comprehensive Income (Loss), Tax December 16, 2023 December 16, 2023 [Member] December 16, 2023 New Accounting Pronouncements Adopted and New Accounting Pronouncements Effective in Future Periods New Accounting Pronouncements, Policy [Policy Text Block] Non-cash tenant allowance amortization Equity Method Investment, Summarized Financial Information, Tenant Allowance Amortization Equity Method Investment, Summarized Financial Information, Tenant Allowance Amortization Shares withheld for taxes and tax benefit of vested shares Share-Based Payment Arrangement, Decrease for Tax Withholding Obligation Gross unrealized holding losses Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Other expenses Other Expenses Measurement Basis [Axis] Measurement Basis [Axis] Net income (loss) per share attributable to common stockholders, basic, (in dollars per share) Earnings Per Share, Basic Adjustment to Compensation: Adjustment to Compensation [Axis] RELATED PARTY TRANSACTIONS Related Party Transactions Disclosure [Text Block] Tejon Ranch Commerce Center - Commercial Tejon Ranch Commerce Center - Commercial [Member] Tejon Ranch Commerce Center - Commercial Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Award Date [Axis] Award Date [Axis] Cost of purchased water (per acre-foot) Cost of Purchased Water, Area Cost of Purchased Water, Area Other Liabilities Other Liabilities [Abstract] Other comprehensive loss Other comprehensive loss Other Comprehensive Income (Loss), Net of Tax Corporate Joint Venture Corporate Joint Venture [Member] Schedule of Segment Information Schedule of Segment Reporting Information, by Segment [Table Text Block] Supplemental executive retirement plan liability (See Note 12) Liability, Pension and Other Postretirement and Postemployment Benefits, Noncurrent Adjustment to Compensation, Amount Adjustment to Compensation Amount Pension Plan Pension Plan [Member] TRC-MRC 3, LLC TRC-MRC 3 LLC [Member] TRC-MRC 3 LLC [Member] Stock compensation expense Share-Based Payment Arrangement, Noncash Expense Employee Stock Option Share-Based Payment Arrangement, Option [Member] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Total Tejon Ranch Co. stockholders’ equity Equity, Attributable to Parent Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-Sale [Table] Other comprehensive loss: Other Comprehensive Income (Loss), Net of Tax [Abstract] Insider Trading Policies and Procedures [Line Items] Total fair value of award Employee and director - expensed Share-Based Payment Arrangement, Expense Common stock, authorized shares (in shares) Common Stock, Shares Authorized Revenues Segment Reporting Information, Revenue for Reportable Segment [Abstract] Goodwill and Intangible Assets Disclosure [Abstract] Goodwill and Intangible Assets Disclosure [Abstract] Excess tax provision (benefit) from stock-based compensation Excess Tax (Expense) Benefit From Stock-Based Compensation Excess Tax (Expense) Benefit From Stock-Based Compensation Real estate development expenditures Payments to Develop Real Estate Assets Avek water for future delivery (in acre-feet) Long-term Water Assets, Water Contract Rights for Future Delivery (Volume) Long-term Water Assets, Water Contract Rights for Future Delivery (Volume) Current Assets: Assets, Current [Abstract] TOTAL LIABILITIES AND EQUITY Liabilities and Equity Transferable water Transferable Water [Member] Transferable water. Real estate and improvements - held for lease, net Real estate and improvements - held for lease, net Inventory, Real Estate, Improvements LIABILITIES AND EQUITY Liabilities and Equity [Abstract] Cover [Abstract] Cover [Abstract] STOCK COMPENSATION - RESTRICTED STOCK AND PERFORMANCE SHARE GRANTS Stock Compensation Restricted Stock and Performance Share Grants [Text Block] Stock compensation restricted stock and performance share grants. Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Maximum Maximum [Member] Schedule of Equity Method Investments [Table] Equity Method Investment [Table] Net loss attributable to non-controlling interest Net Income (Loss) Attributable to Noncontrolling Interest Accounting Policies [Abstract] Accounting Policies [Abstract] Total water held for future use Long-term Water Assets, Banked Water and Water Contract Rights (Volume) Long-term Water Assets, Banked Water and Water Contract Rights (Volume) Net cost of purchased water contracts Finite-Lived Intangible Assets, Net Simulated Monte Carlo share price (in dollars per share) Share based Compensation Arrangement by Share based Payment Award Simulated Price Share based Compensation Arrangement by Share based Payment Award Simulated Price Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Investments in water assets Payments to Acquire Other Investments Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Deficit balance Distributions in Excess of Investment in Unconsolidated Joint Venture Distributions in Excess of Investment in Unconsolidated Joint Venture Gain on sale of property plant and equipment Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Pay vs Performance Disclosure [Line Items] Retirement Benefits [Abstract] Retirement Benefits [Abstract] Additional reimbursement funds Additional Reimbursement Funds Additional reimbursement funds. Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Income (loss) before income tax expense (benefit) Income (loss) before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Entity Shell Company Entity Shell Company East CFD East Community Facilities Districts [Member] -- None. No documentation exists for this element. -- Other liabilities Total Other Liabilities, Noncurrent Property tax payable Accrual for Taxes Other than Income Taxes, Current Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Capitalized Share-Based Payment Arrangement, Amount Capitalized Operating Segments Operating Segments [Member] Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Company Selected Measure Amount Company Selected Measure Amount Comprehensive loss attributable to non-controlling interests Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Line of Credit Facility [Table] Line of Credit Facility [Table] Accrued bonus Accrued Bonuses, Current Comprehensive income (loss) attributable to common stockholders Comprehensive Income (Loss), Net of Tax, Attributable to Parent March 06, 2025 March 06, 2025 [Member] March 06, 2025 Name Measure Name Deferred tax liability Deferred Income Tax Liabilities, Net Expected long-term rate of return on plan assets Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-Term Rate of Return on Plan Assets Long-term water assets (in acre-feet) Long-term Water Assets (Volume) Long-term Water Assets (Volume) Document Fiscal Period Focus Document Fiscal Period Focus Schedule of Other Liabilities Other Liabilities [Table Text Block] Award Timing Method Award Timing Method [Text Block] Receivables, inventories, prepaids and other assets, net Increase (Decrease) in Operating Assets Award Type [Axis] Award Type [Axis] Long-term deferred gains Contract with Customer, Liability, Noncurrent Legal Entity [Axis] Legal Entity [Axis] TRC-MRC 2, LLC TRC-MRC 2 LLC [Member] TRC-MRC 2 LLC [Member] TOTAL ASSETS Identifiable assets Assets Assets Investment, Name [Domain] Investment, Name [Domain] Trading Symbol Trading Symbol Restricted Cash Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block] Executive Vice President and Chief Operating Officer Management [Member] WRMWSD - Contracts with the Company Wheeler Ridge Maricopa Water Storage District Wheeler Ridge Maricopa Water Storage District [Member] Wheeler Ridge Maricopa Water Storage District [Member] Maximum performance (in shares) Performance Awards Granted with Performance Conditions, Maximum Number of Shares to be Issued, at Maximum Performance Performance Awards Granted with Performance Conditions, Maximum Number of Shares to be Issued, at Maximum Performance Service period Defined Benefit Plan, Average Service Period Defined Benefit Plan, Average Service Period Entity Address, City or Town Entity Address, City or Town Operating Activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Tejon Ranch Commerce Center - Multifamily Tejon Ranch Commerce Center - Multifamily [Member] Tejon Ranch Commerce Center - Multifamily Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount AVEK Antelope Valley East Kern Water Agency [Member] Antelope valley east kern water agency. Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Target performance (in shares) Performance Awards Granted with Performance Conditions, Number of Shares to be Issued, at Target Performance Performance Awards Granted with Performance Conditions, Number of Shares to be Issued, at Target Performance Equity in Earnings (Loss) Equity Method Investment Summarized Financial Information, Equity In Earnings (Loss) Equity Method Investment Summarized Financial Information, Equity In Earnings (Loss) Entity Emerging Growth Company Entity Emerging Growth Company Entity Common Stock Shares Outstanding Entity Common Stock, Shares Outstanding Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-Sale [Line Items] Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Level 2 Fair Value, Inputs, Level 2 [Member] Investment in unconsolidated joint ventures Equity Method Investments Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Common stock, outstanding shares (in shares) Beginning balance (in shares) Ending balance (in shares) Common Stock, Shares, Outstanding Accrued capital expenditures included in current liabilities Change In Capital Expenditures Incurred But Not Yet Paid Change In Capital Expenditures Incurred But Not Yet Paid Plan Name [Axis] Plan Name [Axis] Real estate and improvements - held for lease, gross Inventory, Real Estate, Improvements, Gross Inventory, Real Estate, Improvements, Gross PEO PEO [Member] Accrued vacation Accrued Vacation, Current Schedule of Maturities, at Par, of Marketable Securities by Year Investments Classified by Contractual Maturity Date [Table Text Block] Annual fee increase Long Term Water Assets, Purchased, Annual Fee Increase, Percent Long Term Water Assets, Purchased, Annual Fee Increase, Percent Loss before equity in earnings of unconsolidated joint ventures and income tax expense (benefit) Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Changes in operating assets and liabilities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract] Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Expected volatility Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate Retained Earnings Retained Earnings [Member] Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Revenues Revenue from Purchased Water Revenue from Purchased Water Summary of stock grant activity: Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Effective interest rate Debt Instrument, Interest Rate, Effective Percentage Schedule of Accrued liabilities and other current liabilities Schedule of Accrued Liabilities [Table Text Block] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Restatement Determination Date Restatement Determination Date Water Contracts (Dudley-Ridge, Nickel and Tulare) Dudley Ridge, Nickel And Tulare Water Contracts [Member] Dudley Ridge, Nickel And Tulare Water Contracts Share-based Payment Arrangement [Abstract] Share-Based Payment Arrangement [Abstract] Cash, cash equivalents, and restricted cash at beginning of period Cash, cash equivalents, and restricted cash at end of period Total cash, cash equivalents, and restricted cash Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Statement of Operations Income Statement [Abstract] Income tax expense (benefit) Income Tax Expense (Benefit) Funds invested in marketable securities Payments to Acquire Marketable Securities Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Company water bank Long-term Water Assets, Banked Water Held at Company Owned Water Bank (Volume) Long-term Water Assets, Banked Water Held at Company Owned Water Bank (Volume) Total Stockholders' Equity Parent [Member] Net income (loss) Net income (loss) Net income (loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Grapevine Grapevine [Member] Grapevine [Member] SWP Water Contracts State Water Project Contracts [Member] State water project contracts. Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Dudley-Ridge water purchase contract Dudley Ridge Water Rights [Member] Dudley Ridge Water Rights [Member] City Area Code City Area Code Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] All Trading Arrangements All Trading Arrangements [Member] Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Stock grants outstanding beginning of the year at target achievement (in shares) Stock grants outstanding end of period at target achievement (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Schedule Of Equity Method Investment Equity Method Investee Name Axis [Domain] Schedule Of Equity Method Investment Equity Method Investee Name Axis [Domain] Schedule Of Equity Method Investment Equity Method Investee Name Axis [Domain] Investing Activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Net cash provided by (used in) operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Additional costs for future years Improvement Funds, Reimbursement Of Public Infrastructure Costs Improvement Funds, Reimbursement Of Public Infrastructure Costs Related Party Transactions [Abstract] Related Party Transactions [Abstract] Fair Value Debt Securities, Available-for-Sale, Excluding Accrued Interest Equity Method Investments and Joint Ventures [Abstract] Equity Method Investments and Joint Ventures [Abstract] Subsequent Event Subsequent Event [Member] Net amortization and deferral Defined Benefit Plan, Amortization of Gain (Loss) Total Equity Method Investment, Nonconsolidated Investee or Group of Investees [Member] Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] PEO Total Compensation Amount PEO Total Compensation Amount Depreciation and amortization Depreciation Money Market Funds Money Market Funds [Member] TRCC-East TRCC-East [Member] TRCC-East [Member] Income taxes receivable Income Taxes Receivable OTHER LIABILITIES Other Liabilities Disclosure [Text Block] Equity Components [Axis] Equity Components [Axis] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Restricted stock issuance Stock Issued During Period, Value, Restricted Stock Award, Gross Petro Travel Plaza Holdings, LLC Petro Travel Plaza Holdings, LLC Petro Travel Holdings Llc Plaza [Member] Petro travel holdings llc plaza. Fair market value of investment securities below their cost basis Debt Securities, Available for Sale Securities, Fair Market Value Exceeds Cost Basis, by Amount Debt Securities, Available for sale securities, fair market value exceeds cost basis, by amount. Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Number of reportable segments Number of Reportable Segments Non-cash investing activities Supplemental Cash Flow Information [Abstract] Segment Reporting Information [Line Items] Revenue from External Customer [Line Items] June 20, 2025 June 20, 2025 [Member] June 20, 2025 Other Performance Measure, Amount Other Performance Measure, Amount Entity Address, State or Province Entity Address, State or Province Related Party [Domain] Related and Nonrelated Parties [Domain] Total current liabilities Liabilities, Current Restricted stock issuance (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Gross Individual: Individual [Axis] Financial Instruments Fair Value of Financial Instruments, Policy [Policy Text Block] Restricted cash (included in prepaid expenses and other current assets) Restricted cash Restricted Cash Additional paid-in capital Additional Paid in Capital, Common Stock Entity [Domain] Entity [Domain] Net cash used in investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Investments in unconsolidated joint ventures Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Total water held for future use and purchased water contracts Long Term Water Assets, Contracts with Company Long Term Water Assets, Contracts with Company Document Fiscal Year Focus Document Fiscal Year Focus Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Ranch operations Ranch Operations Ranch Operations [Member] Ranch Operations [Member] Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Entity Interactive Data Current Entity Interactive Data Current Equity Method Investment, Nonconsolidated Investee [Axis] Equity Method Investment, Nonconsolidated Investee [Axis] Other Other Employee-related Liabilities, Current Plan Name [Domain] Plan Name [Domain] Cost Reported Value Measurement [Member] Current liabilities Increase (Decrease) in Operating Liabilities Total compensation cost not yet recognized, period for recognition Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Real Estate [Abstract] Real Estate [Abstract] Reconciling items: Segment Reconciliation [Abstract] REPORTING SEGMENTS AND RELATED INFORMATION Segment Reporting Disclosure [Text Block] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Ownership [Domain] Ownership [Domain] Schedule of Components of Net Periodic Pension Cost Schedule of Net Benefit Costs [Table Text Block] Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Selling, general and administrative expenses Selling, General and Administrative Expense Five West Parcel Llc Five West Parcel Llc [Member] Five west parcel llc. Depreciation and amortization Depreciation, Depletion and Amortization Other assets Other Assets, Noncurrent Schedule of Performance Share Grants with Performance Conditions Schedule of Share-based Payment Award, Performance Share Awards Granted, by Performance Conditions [Table Text Block] Schedule of Share-based Payment Award, Performance Share Awards Granted, by Performance Conditions [Table Text Block] Entity Central Index Key Entity Central Index Key PEO Name PEO Name Revenues Revenues Revenues Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Revolving Credit Facility Revolving Credit Facility [Member] Schedule Of Equity Method Investment Equity Method Investee Name Axis [Axis] Schedule Of Equity Method Investment Equity Method Investee Name Axis [Axis] Schedule Of Equity Method Investment Equity Method Investee Name Axis TRC-MRC 1, LLC TRC-MRC 1 LLC [Member] TRC-MRC 1 LLC [Member] Schedule of Defined Benefit Plans Disclosures [Table] Defined Benefit Plan [Table] Arrangement Duration Trading Arrangement Duration Excess joint venture distributions and other (See Note 14) Other Sundry Liabilities, Noncurrent Real estate - resort/residential Resort and Residential Real Estate [Member] Resort and Residential Real Estate [Member] Deferred income Contract with Customer, Liability, Current Business Segments [Axis] Segments [Axis] DMB DMB Pacific LLC [Member] DMB Pacific LLC [Member] Exercise Price Award Exercise Price Entity Filer Category Entity Filer Category Local Phone Number Local Phone Number Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Schedule of Long Lived Assets Held-for-sale [Table] Long-Lived Asset, Held-for-Sale [Table] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Cost of sales Cost of sales of water Cost of Purchased Water Number of directors Number of Directors Number of Directors ASSETS Assets [Abstract] Current investment policy targets: Defined Benefit Plan, Plan Assets, Allocations [Abstract] Credit Facility [Axis] Credit Facility [Axis] Mountain Village Tejon Mountain Village Llc [Member] Tejon mountain village llc. Unrealized loss on available-for-sale securities OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, before Tax Underlying Security Market Price Change Underlying Security Market Price Change, Percent (Cost)/earnings components: Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] Debt Instrument [Axis] Debt Instrument [Axis] RETIREMENT PLANS Retirement Benefits [Text Block] Credit Facility [Domain] Credit Facility [Domain] Costs Finite-Lived Intangible Assets, Gross Tejon Ranch Co. stockholders’ equity Equity, Attributable to Parent [Abstract] Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Entity Address, Address Line One Entity Address, Address Line One Entity Address, Address Line Two Entity Address, Address Line Two Total water held for future use at cost Total cost of water held for future use Tangible Water Assets, Banked Water and Water Contract Rights Tangible Water Assets, Banked Water and Water Contract Rights Accumulated Other Comprehensive (Loss) Income AOCI Attributable to Parent [Member] Investment, Name [Axis] Investment, Name [Axis] Stated interest rate Debt Instrument, Interest Rate, Stated Percentage Shares withheld for taxes and tax benefit of vested shares (in shares) Share-Based Payment Arrangement, Shares Withheld for Tax Withholding Obligation Schedule of Real Estate Schedule of Real Estate Properties [Table Text Block] Measurement period from entitlement achievement date Contract Termination, Incentive Fee Calculation, Measurement Period From Entitlement Achievement Date Contract Termination, Incentive Fee Calculation, Measurement Period From Entitlement Achievement Date Real estate - commercial/industrial Commercial and Industrial Commercial and Industrial [Member] Commercial and industrial. Ownership [Axis] Ownership [Axis] Banked water and water for future delivery Banked Water and Water for Future Delivery [Member] Banked water and water for future delivery. Mineral resources Mineral Resources Mineral Resources [Member] Mineral Resources [Member] Name of Property [Domain] Name of Property [Domain] Fair Value as of Grant Date Award Grant Date Fair Value TRC-MRC 4, LLC TRC-MRC 4 LLC [Member] TRC-MRC 4 LLC Entity Registrant Name Entity Registrant Name Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Total net periodic pension cost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Municipal notes Municipal Bonds [Member] Special taxes paid Taxes, Other Common stock equivalents (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements New stock grants/additional shares (in shares) Shares granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Total costs and expenses Multifamily expenses Corporate expenses Commercial/industrial expenses Total resort/residential expenses Costs and Expenses Expired/forfeited grants (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period Total compensation cost not yet recognized Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Related Party Transaction [Line Items] Related Party Transaction [Line Items] Document Quarterly Report Document Quarterly Report Long Lived Assets Held-for-sale, Name [Domain] Long-Lived Assets Held-for-Sale, Name [Domain] Revision of Prior Period [Domain] Revision of Prior Period [Domain] Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Counterparty Name [Domain] Counterparty Name [Domain] Amortization of discount of marketable securities Accretion (Amortization) of Discounts and Premiums, Investments Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Accrued interest receivable balance Accrued Investment Income Receivable Number of real estate properties delivered Number Of Real Estate Properties Delivered Number Of Real Estate Properties Delivered Related Party [Axis] Related and Nonrelated Parties [Axis] Interest cost Defined Benefit Plan, Interest Cost Title Trading Arrangement, Individual Title Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Schedule of Finite-Lived Intangible Assets Schedule of Finite-Lived Intangible Assets [Table Text Block] Restatement Determination Date: Restatement Determination Date [Axis] Majestic Realty Co. Majestic Realty Co. [Member] Majestic Realty Co. [Member] Non-PEO NEO Non-PEO NEO [Member] Commercial/industrial revenues and equity in earnings of unconsolidated joint ventures Revenues and Income (Loss) from Equity Method Investments Revenues and Income (Loss) from Equity Method Investments Taxes on vested stock grants Proceeds from (Payment for) Other Financing Activity Employee 1998 Plan Stock Incentive Plan 1998 [Member] Stock incentive plan. Schedule of Assumptions Used to Determine The Price of Market-Based Performance Condition Grants Schedule of Share-based Payment Award, Equity Instruments Other than Options, Valuation Assumptions [Table Text Block] Schedule of Share-based Payment Award, Equity Instruments Other than Options, Valuation Assumptions [Table Text Block] Schedule of Water Revenues and Cost of Sales Schedule of Water Revenues and Cost of Sales [Table Text Block] Schedule of Water Revenues and Cost of Sales [Table Text Block] Marketable securities, with unrecognized gains Gross unrealized holding gains Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax Name Trading Arrangement, Individual Name Award Type [Domain] Award Type [Domain] Non-controlling interest Equity, Attributable to Noncontrolling Interest Equity Awards Adjustments Equity Awards Adjustments [Member] Area of building owned and leased Lease of Building Lease of building. Real estate development (includes $129,423 at March 31, 2026 and $128,549 at December 31, 2025, attributable to CFL (Note 14)) Real estate development Inventory, Real Estate, Land and Land Development Costs Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Compensation Amount Outstanding Recovery Compensation Amount Additional bond debt authorized to be sold in future Debt instrument face amount Debt Instrument, Face Amount Recharged water Long-term Water Assets, Recharged Project Water (Volume) Long-term Water Assets, Recharged Project Water (Volume) Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] REAL ESTATE Real Estate Disclosure [Text Block] Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Certificates of deposit Certificates of Deposit [Member] Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Fair Value Estimate of Fair Value Measurement [Member] Number of tenants Joint Venture, Number Of Tenants Joint Venture, Number Of Tenants Retirement Plan Type [Domain] Retirement Plan Type [Domain] MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Assumptions used in determining periodic pension cost: Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract] Name Awards Close in Time to MNPI Disclosures, Individual Name Long-term acres of land to joint venture Long-Term Acres of Land to Joint Venture At Fair Market Value Long-Term Acres of Land to Joint Venture At Fair Market Value U.S. Treasury and agency notes U.S. Treasury and agency notes US Treasury and Government Short-Term Debt Securities [Member] Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Consulting agreement term Related Party Transaction, Term Related Party Transaction, Term Revenues: Revenues [Abstract] Number of acres for development Development of Building Development of building. 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Proceeds from sale of property plant and equipment Proceeds from Sale, Real Estate, Other, Held-for-Investment Company Selected Measure Name Company Selected Measure Name Fair Value Measurement [Domain] Fair Value Measurement [Domain] LINE OF CREDIT AND LONG-TERM DEBT Debt Disclosure [Text Block] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Trade accounts payable Accounts Payable, Current Amount paid for water contracts Operating Lease, Payments Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Other comprehensive loss before taxes Other comprehensive loss before taxes Other Comprehensive Income (Loss), before Tax All Executive Categories All Executive Categories [Member] Stockholders' Equity Note [Abstract] Stockholders' Equity Note [Abstract] Common stock, $0.50 par value per share: authorized shares - 50,000,000 issued and outstanding shares - 26,893,955 at March 31, 2026 and 26,916,837 at December 31, 2025 Common Stock, Value, Issued COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Diluted shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Diluted Commitments and contingencies (Note 11) Commitments and Contingencies Farming Farming and Agriculture [Member] Farming and agriculture. 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