Area of real estate property Area of Real Estate Property New stock grants/additional shares due to achievement in excess of target (in shares) Shares granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Machinery, furniture fixtures and other equipment Other Machinery and Equipment [Member] Acres of land related to land liens Acres of Land Related to Land Liens Acres of land related to land liens. Document Type Document Type Total revenues and other income Revenue and Other Income Revenue and Other Income Auditor Attestation Flag ICFR Auditor Attestation Flag Other income (loss) Other Nonoperating Income (Expense) Comprehensive income attributable to common stockholders Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Change in benefit obligation - Pension Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Related Party [Axis] Related Party [Axis] Payables and Accruals [Abstract] Payables and Accruals [Abstract] Change in Plan Assets Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] Marketable Securities Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Stock compensation costs Share-based Compensation Arrangement by Share-based Payment Award, Compensation Costs Share-based Compensation Arrangement by Share-based Payment Award, Compensation Costs Business Segments [Axis] Segments [Axis] Retirement Plans Retirement Benefits [Text Block] Maturities and sales of marketable securities Proceeds from Sale and Maturity of Marketable Securities Contractual obligation for future water payments Contractual Obligation Benefits/expenses paid Defined Benefit Plan, Plan Assets, Benefits Paid Statistical Measurement [Domain] Statistical Measurement [Domain] LIABILITIES AND EQUITY Liabilities and Equity [Abstract] 2025 Lessor, Operating Lease, Payment to be Received, Year Five Non-cash tenant allowance amortization Equity Method Investment, Summarized Financial Information, Tenant Allowance Amortization Equity Method Investment, Summarized Financial Information, Tenant Allowance Amortization Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Thereafter Lessor, Operating Lease, Payment to be Received, after Year Five Deferred tax liability Deferred Income Tax Liabilities, Net Interest Rate Swap Derivative Instruments and Hedging Activities Disclosure [Text Block] Security Exchange Name Security Exchange Name Fair value of plan assets at beginning of year Fair value of plan assets at end of year Fair value of plan assets Defined Benefit Plan, Plan Assets, Amount Operating (loss) income Segment profits Operating Income (Loss) Consumer price per acre (per acre-foot) Cost of Purchased Water, Area Cost of Purchased Water, Area Pistachios Pistachios [Member] Pistachios [Member] TRCC/Rock Outlet Center, LLC TRCC/Rock Outlet Center [Member] TRCC/Rock Outlet Center [Member] March 11 2020 March 11 2020 [Member] March 11 2020 State deferred taxes Deferred Tax Assets, State Taxes Total current liabilities Liabilities, Current Curtailments Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment Performance share grants Performance Shares [Member] Almonds Almonds [Member] Almonds [Member] Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Variable Rate [Domain] Variable Rate [Domain] 2025 Defined Benefit Plan, Expected Future Benefit Payment, Year Five Variable Rate [Axis] Variable Rate [Axis] Commitments and contingencies Commitments and Contingencies Shares withheld for taxes and tax benefit of vested shares Share-based Payment Arrangement, Decrease for Tax Withholding Obligation ASSETS Assets [Abstract] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] TRC-MRC 3, LLC TRC-MRC 3 LLC [Member] TRC-MRC 3 LLC [Member] Investment, Name [Axis] Investment, Name [Axis] Accounting Policies [Abstract] Accounting Policies [Abstract] Ranchcorp Subsidiaries [Member] Entity Address, State or Province Entity Address, State or Province Vested grants (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Amount paid for water contracts Operating Lease, Payments Income tax at statutory rate Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount Other comprehensive (loss) income before taxes Other Comprehensive Income (Loss), before Tax Trade accounts payable Accounts Payable, Current Letter of credit renewal period Letter of Credit Renewal Period Letter of credit renewal period. 2023 Long-Term Debt, Maturity, Year Three Accrued Liabilities and Other Accounts Payable and Accrued Liabilities Disclosure [Text Block] Retained earnings Retained Earnings (Accumulated Deficit) Depreciation Deferred Tax Liabilities, Property, Plant and Equipment 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) Deferred gain on sale Equity Method Investment, Deferred Gain on Sale Transferable water Transferable water Transferable Water [Member] Transferable water. Transaction costs Contribution of Property, Transaction Costs Contribution of Property, Transaction Costs Investment in unconsolidated joint ventures Payments to Acquire Interest in Joint Venture Income tax payments Income Taxes Paid Equity: Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Compensation cost not yet recognized Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount 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. Long Lived Assets Held For Sale [Line Items] Long Lived Assets Held-for-sale [Line Items] Major Customers [Axis] Customer [Axis] Current Current State and Local Tax Expense (Benefit) Real estate development (includes $108,600 at December 31, 2020 and $104,491 at December 31, 2019, attributable to Centennial Founders, LLC, Note 17) Real estate development Real estate development Inventory, Real Estate, Land and Land Development Costs Beginning balance (in shares) Ending balance (in shares) Shares, Outstanding Benefit plan adjustments Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment and Tax 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) 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 Other comprehensive (loss) income: Other Comprehensive Income (Loss), Net of Tax [Abstract] Excess distributions resulting in deficit balance Distributions in Excess of Investment in Unconsolidated Joint Venture Distributions in Excess of Investment in Unconsolidated Joint Venture Common stock, par value per share (in dollars per share) Common Stock, Par or Stated Value Per Share 2023 Defined Benefit Plan, Expected Future Benefit Payment, Year Three Other liabilities Other liabilities Other Liabilities, Noncurrent Deferred tax assets Deferred Income Tax Assets, Net Additional reimbursement funds Additional Reimbursement Funds Additional reimbursement funds. Stock compensation APIC, Share-based Payment Arrangement, Increase for Cost Recognition Water contracts and related costs Related Party Transaction, Amounts of Transaction East CFD East Community Facilities Districts [Member] -- None. No documentation exists for this element. -- Inventories Inventories Inventory, Net Thereafter Long-Term Debt, Maturity, after Year Five Other Other Inventory, Net of Reserves Percentage of revenue Concentration Risk, Percentage Geographical [Domain] Geographical [Domain] Settlement recognition Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement Estimated contribution to the pension plan Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Cash and Cash Equivalents, Period Increase (Decrease) [Abstract] Cash and Cash Equivalents, Period Increase (Decrease) [Abstract] Amortization of net gain/(loss) Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year State deferred taxes Deferred Tax Liabilities, State Taxes Deferred Tax Liabilities, State Taxes Statement [Line Items] Statement [Line Items] Number of members Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures, Number of Members Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures, Number of Members Entity Voluntary Filers Entity Voluntary Filers Long-term water assets (Volume) Long-term water assets (Volume) (in acre-feet) Long-term Water Assets (Volume) Long-term Water Assets (Volume) Statement [Table] Statement [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Interest cost Interest cost Defined Benefit Plan, Interest Cost Statistical Measurement [Axis] Statistical Measurement [Axis] Amounts expected to be recognized as component of net periodic pension costs during the next fiscal year: Defined Benefit Plan, Expected Amortization, Next Fiscal Year [Abstract] Credit Facility [Axis] Credit Facility [Axis] Collective Funds Equity Funds [Member] Excess tax benefit of stock-based compensation Excess Tax Benefit of Stock-Based Compensation, Operating Activities Excess Tax Benefit of Stock-Based Compensation, Operating Activities Deferred income taxes Deferred Income Taxes and Tax Credits Assumptions used in determining actuarial present value of projected benefits obligation: Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract] Schedule of weighted average number of shares outstanding Schedule of Weighted Average Number of Shares [Table Text Block] TRC-MRC 2, LLC TRC-MRC 2 LLC [Member] TRC-MRC 2 LLC [Member] 18-19 West, LLC Eighteen Nineteen West Llc [Member] Eighteen nineteen west llc. Marketable Securities Marketable Securities, Policy [Policy Text Block] Information pretaining to assets of the business segments Segment Reporting Information, Additional Information [Abstract] Wheeler Ridge Maricopa Water Storage District Wheeler Ridge Maricopa Water Storage District [Member] Wheeler Ridge Maricopa Water Storage District [Member] Entity Small Business Entity Small Business Principles of Consolidation Consolidation, Policy [Policy Text Block] 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 Farming inventories Agricultural Related Inventory, Net of Reserves Agricultural Related Inventory, Net of Reserves Average service period Defined Benefit Plan, Average Service Period Defined Benefit Plan, Average Service Period Joint venture allocations Deferred Tax Assets, Equity Method Investments Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Line of Credit and Long-term Debt Debt Disclosure [Text Block] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Net proceeds from rights offering Proceeds from Issuance of Common Stock Amendment Flag Amendment Flag AVEK Antelope Valley East Kern Water Agency [Member] Antelope valley east kern water agency. 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 Weighted Average Number of Shares Outstanding, Diluted [Abstract] Weighted Average Number of Shares Outstanding, Diluted [Abstract] Percentage rent Operating Lease, Lease Income, Percentage Rent Operating Lease, Lease Income, Percentage Rent Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Equity in Earnings (Loss) Equity Method Investment Summarized Financial Information, Equity In Earnings (Loss) Equity Method Investment Summarized Financial Information, Equity In Earnings (Loss) Purchase price, increase amount Investment in Joint Venture Purchase Price Increase Amount Investment in Joint Venture Purchase Price Increase Amount Deferred income tax assets: Deferred Tax Assets, Gross [Abstract] Corporate expenses Corporate, Non-Segment [Member] Accrued liabilities and other Total Other Accrued Liabilities, Current Bond debt sold by TRPFFA Long-term Line of Credit Current investment policy targets: Defined Benefit Plan, Plan Assets, Allocations [Abstract] Funded status: Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract] Defined Benefit Plan, Plan Assets, Category [Axis] Defined Benefit Plan, Plan Assets, Category [Axis] Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Entity Central Index Key Entity Central Index Key Related Party [Domain] Related Party [Domain] Purchase of assets Proceeds from Sale of Building to Third Party Proceeds from Sale of Building to Third Party Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] Long Lived Assets Held-for-sale, Name [Domain] Long Lived Assets Held-for-sale, Name [Domain] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Marketable securities - available-for-sale Debt Securities, Available-for-sale, Current Derivative Instrument [Axis] Derivative Instrument [Axis] Accrued capital and water expenditures included in current liabilities Change In Capital Expenditures Incurred But Not Yet Paid Change In Capital Expenditures Incurred But Not Yet Paid Real estate and improvements - held for lease, net Inventory, Real Estate, Improvements, Gross Inventory, Real Estate, Improvements, Gross Financial Instruments [Domain] Financial Instruments [Domain] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Investments in Unconsolidated Joint Ventures Equity Method Investments [Policy Text Block] Schedule of finite-lived intangible assets Schedule of Finite-Lived Intangible Assets [Table Text Block] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Borrowings on line of credit Proceeds from Short-term Debt Annual fee increase, percent Long Term Water Assets, Purchased, Annual Fee Increase, Percent Long Term Water Assets, Purchased, Annual Fee Increase, Percent Standby letter of credit Standby Letters of Credit [Member] Interest Rate Swap Agreements Derivatives, Policy [Policy Text Block] Executive Vice President and Chief Operating Officer Management [Member] Geographical [Axis] Geographical [Axis] Permanent differences Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Number of acres for development Contribution for Joint Venture for Future Development Contribution for joint venture for future development. Segment [Domain] Segment [Domain] Segments [Domain] Interest rate swap Deferred Tax Assets, Derivative Instruments Revenues Revenue from Purchased Water Revenue from Purchased Water with unrecognized gains Gross unrealized holding gains Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] 2024 Long-Term Debt, Maturity, Year Four Property, Plant and Equipment, Type [Axis] Long-Lived Tangible Asset [Axis] Components of segment revenues Revenue from External Customers by Products and Services [Table Text Block] Entity Common Stock Shares Outstanding Entity Common Stock, Shares Outstanding Total changes Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax Financing Activities Net Cash Provided by (Used in) Financing Activities [Abstract] 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) Special taxes paid Taxes, Other Current Current Federal Tax Expense (Benefit) Notional Amount Derivative, Notional Amount Accrued bonus Accrued Bonuses, Current Stockholders' Equity Note [Abstract] Stockholders' Equity Note [Abstract] Deferred gains Deferred Tax Liabilities, Tax Deferred Income Deferred revenues Deferred Tax Assets, Deferred Income Grapevine Grapevine [Member] Grapevine [Member] Other assets Other Assets, Noncurrent Investment in Unconsolidated and Consolidated Joint Ventures Equity Method Investments and Joint Ventures Disclosure [Text Block] Plan Name [Axis] Plan Name [Axis] SWP contracts State Water Project Contracts [Member] State water project contracts. Federal tax refunds received Proceeds from Income Tax Refunds State State and Local Income Tax Expense (Benefit), Continuing Operations Reporting Segments and Related Information Segment Reporting Disclosure [Text Block] Dudley-Ridge water rights Dudley Ridge Water Rights [Member] Dudley Ridge Water Rights [Member] Concentration Risk [Table] Concentration Risk [Table] TOTAL ASSETS Identifiable Assets Assets Assets Related Party Transactions Related Party Transactions Disclosure [Text Block] Los Angeles, California Los Angeles, California [Member] Los Angeles, California [Member] Revenue Revenue from Contract with Customer Benchmark [Member] Summary of changes in benefit obligations and plan assets Schedule of Net Funded Status [Table Text Block] Vineyards and orchards Vineyards and Orchards [Member] Vineyards and Orchards [Member] Pension adjustment Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Pensions Other changes in plan assets and benefit obligations recognized in other comprehensive income: Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract] Stock grants outstanding beginning of the year at target achievement (in shares) Stock grants outstanding at target achievement (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Title of 12(b) Security Title of 12(b) Security Schedule of accrued liabilities Schedule of Accrued Liabilities [Table Text Block] Net cost of purchased water contracts Finite-Lived Intangible Assets, Net Expected annual benefit payments based on actuarial estimates: Defined Benefit Plan, Expected Future Benefit Payment [Abstract] Securities available for sale OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax Leases Lessor, Operating Leases [Text Block] Investments, Debt and Equity Securities [Abstract] Investments, Debt and Equity Securities [Abstract] 2022 Lessor, Operating Lease, Payment to be Received, Year Two Debt consists of: Long-term Debt, by Current and Noncurrent [Abstract] Credit Risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Depreciation and amortization Depreciation and Amortization Depreciation, Depletion and Amortization Excess stock compensation expense Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount Pastoria Energy Facility, LLC PEF Pastoria Energy Facility, LLC [Member] Pastoria Energy Facility, LLC [Member] Components of provision (benefit) for income taxes Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Product and Service [Axis] Product and Service [Axis] TRCC-East TRCC-East [Member] TRCC-East [Member] Total liabilities Liabilities Land and Building Land and Building [Member] Weighted-average recognition period of compensation cost Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Petro Travel Plaza Holdings LLC Petro Travel Holdings Llc Plaza [Member] Petro travel holdings llc plaza. Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Fair market value of investment securities exceeds 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. Retirement Plan Type [Axis] Retirement Plan Type [Axis] Percent of water used within the adjudication boundary Loss Contingency, Settlement, Percent of Water Use Within the Adjudication Boundary Loss Contingency, Settlement, Percent of Water Use Within the Adjudication Boundary Vineyards and Orchards Agriculture, Policy [Policy Text Block] 2022 Long-Term Debt, Maturity, Year Two Cost of sales allocations Deferred Tax Liabilities, Cost of Sales Allocations Deferred Tax Liabilities, Cost of Sales Allocations Components of provision (benefit) for income taxes: Income Tax Expense (Benefit), Continuing Operations, by Jurisdiction [Abstract] Schedule of Related Party Transactions, by Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Total Debt Securities, Available for Sale Securities Maturities at Par Debt Securities, Available for sale securities maturities, at par. Level 1 Level 1 Fair Value, Inputs, Level 1 [Member] Real Estate [Abstract] Real Estate [Abstract] Land and land improvements Land and Land Improvements [Member] 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] Contract-based intangible assets Contract-Based Intangible Assets [Member] Additional Paid-In Capital Additional Paid-in Capital [Member] Schedule of quarterly operating results Quarterly Financial Information [Table Text Block] Operating Segments Operating Segments [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 Adjustments to reconcile net (loss) income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Gain on sale of real estate Gain on sale of real estate Gains (Losses) on Sales of Investment Real Estate Litigation Case [Axis] Litigation Case [Axis] Corporate notes Corporate Note Securities [Member] Fair Values of Financial Instruments Fair Value of Financial Instruments, Policy [Policy Text Block] Investment in unconsolidated joint ventures Equity Method Investments Common stock, outstanding shares (in shares) Common Stock, Shares, Outstanding Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Ranch operations Ranch Operations [Member] Ranch Operations [Member] State income taxes, net of Federal benefit Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount Income before income taxes Operating results from commercial and unconsolidated joint ventures Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Letters of credit outstanding amount Letters of Credit Outstanding, Amount Common stock, authorized shares (in shares) Common Stock, Shares Authorized Concentration Risk Type [Axis] Concentration Risk Type [Axis] Common stock equivalents-stock options, grants (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Property and equipment, gross Property, Plant and Equipment, Gross Deferred Deferred Federal Income Tax Expense (Benefit) 2022 Defined Benefit Plan, Expected Future Benefit Payment, Year Two State: State and Local Income Tax Expense (Benefit), Continuing Operations [Abstract] Schedule of information pertaining to assets of segments Schedule of Segment Reporting Information, by Segment [Table Text Block] Funded status - liability Defined Benefit Plan, Funded (Unfunded) Status of Plan Refunds Effective Income Tax Rate Reconciliation, Tax Exempt Income, Amount Schedule of real estate Schedule of Real Estate Properties [Table Text Block] Accrued vacation Accrued Vacation, Current Farming revenue adjustments for differences between original estimates and actual revenues received Farming Revenue, Adjustment to Final Settlement Price Farming Revenue, Adjustment to Final Settlement Price Estimated Fair Value Estimate of Fair Value Measurement [Member] Income Statement [Abstract] Income Statement [Abstract] Accumulated Other Comprehensive Loss AOCI Attributable to Parent [Member] Gain (loss) on sale of properties Gain (Loss) on Disposition of Assets Summary of maturities, at par, of marketable securities by year Investments Classified by Contractual Maturity Date [Table Text Block] Pension and supplemental executive retirement plan liability Liability, Pension and Other Postretirement and Postemployment Benefits, Noncurrent Quarterly Financial Information [Line Items] Quarterly Financial Information [Line Items] [Line Items] for Quarterly Financial Information [Table] Five West Parcel, LLC Five West Parcel Llc [Member] Five west parcel llc. Changes, net of taxes Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Name of Property [Domain] Name of Property [Domain] Summary 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] Construction loan percent of costs Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures, Construction Loan Costs, Percent Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures, Construction Loan Costs, Percent Use of Estimates Use of Estimates, Policy [Policy Text Block] Schedule of Long Lived Assets Held-for-sale [Table] Schedule of Long Lived Assets Held-for-sale [Table] Current Assets: Assets, Current [Abstract] TRC-MRC 1, LLC TRC-MRC 1 LLC [Member] TRC-MRC 1 LLC [Member] Consolidated Entities [Axis] Consolidated Entities [Axis] Comprehensive (loss) income attributable to common stockholders Comprehensive Income (Loss), Net of Tax, Attributable to Parent Reconciliation of revenues, segment profits (losses) and net income (loss) Reconciliation of Revenue and Operating Profit (Loss) from Segments to Consolidated [Table Text Block] Reconciliation of Revenue and Operating Profit (Loss) from Segments to Consolidated [Table Text Block] DMB Pacific LLC DMB Pacific LLC [Member] DMB Pacific LLC [Member] Documents Incorporated by Reference Documents Incorporated by Reference [Text Block] Reconciliation of income tax expense from statutory Federal income tax rate Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] 2021 Long-Term Debt, Maturity, Year One Rate of increase in future compensation levels Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase Distance from city Property Border, Distance to Major City Property Border, Distance to Major City Counterparty Name [Domain] Counterparty Name [Domain] Real estate and equipment expenditures Payments to Acquire Property, Plant, and Equipment Legal Entity [Axis] Legal Entity [Axis] City Area Code City Area Code Consolidation Items [Domain] Consolidation Items [Domain] Document Period End Date Document Period End Date Stock Grants Restricted Stock and Performance Shares [Member] Stock grants for restricted stock and performance shares. Mountain Village Tejon Mountain Village Llc [Member] Tejon mountain village llc. Actual return on plan assets Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss) Vineyards and Other Farming Related Assets Vineyards and Other Farming Related Assets [Member] Vineyards and Other Farming Related Assets [Member] Equity in earnings of unconsolidated joint ventures, net Equity in earnings of unconsolidated joint ventures, net Equity in unconsolidated joint ventures, net Equity in earnings of unconsolidated joint ventures Income (Loss) from Equity Method Investments Current investment mix Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage Other Liabilities Other Liabilities Disclosure [Text Block] Net (loss) income Net (loss) income Net income (loss) Net Income (Loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net deferred income tax (liability) asset Deferred Tax Assets (Liabilities), Gross Deferred Tax Assets (Liabilities), Gross (Loss) income from operations before equity in earnings of unconsolidated joint ventures Operating results Operating results Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Long-Lived Assets Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block] Total water held for future use at cost Total cost water held for future use Tangible Water Assets, Banked Water and Water Contract Rights Tangible Water Assets, Banked Water and Water Contract Rights Quarterly Financial Information Disclosure [Abstract] Quarterly Financial Information Disclosure [Abstract] Promissory note Notes Payable, Other Payables [Member] Thereafter Defined Benefit Plan, Expected Future Benefit Payment, after Year Five for Next Five Years Components of inventories Schedule of Inventory, Current [Table Text Block] Capitalized Share-based Payment Arrangement, Amount Capitalized Components of water assets Disclosure of Long Lived Assets Held-for-sale [Table Text Block] Summary of stock compensation costs for employee and NDSI plans Share-based Payment Arrangement, Cost by Plan [Table Text Block] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Stock compensation expense Share-based Payment Arrangement, Noncash Expense Summary of amounts expected to be recognized as component of net periodic pension costs during the next fiscal year Schedule of Amounts in Accumulated Other Comprehensive Income (Loss) to be Recognized over Next Fiscal Year [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 [Member] Commercial and industrial. Entity [Domain] Entity [Domain] Taxes on vested stock grants Proceeds from (Payments for) Other Financing Activities 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 [Member] Mineral Resources [Member] Restricted stock issuance (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Gross Cover [Abstract] Inventories consist of: Inventory, Net, Items Net of Reserve Alternative [Abstract] Summary of available-for-sale securities Debt Securities, Available-for-sale [Table Text Block] Unaudited Quarterly Operating Results Quarterly Financial Information [Text Block] Distribution of earnings from unconsolidated joint ventures Proceeds from Equity Method Investment, Distribution Property and equipment useful life Property, Plant and Equipment, Useful Life Total Long-term Debt Federal Federal Income Tax Expense (Benefit), Continuing Operations Service cost Defined Benefit Plan, Service Cost Amortization of premium (discount) on marketable securities Accretion (Amortization) of Discounts and Premiums, Investments Long-Term Water Assets Long-term Water Assets [Policy Text Block] Long-term Water Assets [Policy Text Block] Interest cost Defined Benefit Plan, Expected Interest Cost, Next Fiscal Year Defined Benefit Plan, Expected Interest Cost, Next Fiscal Year Gain on sale of real estate Gains (Losses) on Sales of Other Real Estate Net deferred taxes Deferred Tax Assets, Net Term Loan Medium-term Notes [Member] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Settled Litigation Settled Litigation [Member] Total available-for-sale securities Debt Securities, Available-for-sale Total expenses Costs and expenses Corporate expenses Commercial expenses Costs and Expenses Award Date [Domain] Award Date [Domain] Letter of credit period Letter of credit period Letter of credit period. Equity Components [Axis] Equity Components [Axis] Share-based Payment Arrangement [Abstract] Share-based Payment Arrangement [Abstract] Number of joint ventures Variable Interest Entity, Number of Entities Consolidated Variable Interest Entity, Number of Entities Consolidated Total deferred income tax assets Deferred Tax Assets, Gross Minimum Minimum [Member] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Segment Profit (Loss) Segment Profit (Loss), Excluding Equity in Earnings Segment Profit (Loss), Excluding Equity in Earnings Majestic Realty Co. Majestic Realty Co. [Member] Majestic Realty Co. [Member] Consolidated Entities [Domain] Consolidated Entities [Domain] Land Land [Member] Revenue from External Customer [Line Items] Revenue from External Customer [Line Items] Award Date [Axis] Award Date [Axis] Percentage of rent billings deferred Rent Billings Percentage Deferred Rent Billings Percentage Deferred Federal: Federal Income Tax Expense (Benefit), Continuing Operations [Abstract] Commercial 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 Defined Benefit Plan, Plan Assets, Category [Domain] Defined Benefit Plan, Plan Assets, Category [Domain] Equities Defined Benefit Plan, Equity Securities [Member] 1998 Plan Stock Incentive Plan 1998 [Member] Stock incentive plan. Net loss attributable to non-controlling interest Comprehensive loss attributable to non-controlling interests Net Income (Loss) Attributable to Noncontrolling Interest Equity Method Investments and Joint Ventures [Abstract] Equity Method Investments and Joint Ventures [Abstract] Net amortization and deferral Net amortization and other Defined Benefit Plan, Amortization of Gain (Loss) 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] Non-cash profits recognized from land contribution Gain (Loss) on Disposition of Other Assets Entity Interactive Data Current Entity Interactive Data Current Total net periodic pension earnings/(cost) Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Non-cash write-off of leasing assets Abandonment Expense Abandonment Expense Schedule of fair value of plan assets by investment type Schedule of Allocation of Plan Assets [Table Text Block] Revenues: Revenues [Abstract] Straight line rent Deferred Tax Liabilities, Straight Line Rent Deferred Tax Liabilities, Straight Line Rent Contribution to unconsolidated joint venture Contribution of property Contribution of Property Operating Activities Net Cash Provided by (Used in) Operating Activities [Abstract] Equity Stockholders' Equity Note Disclosure [Text Block] Components of deferred tax assets and liabilities: Components of Deferred Tax Assets and Liabilities [Abstract] Area of building owned and leased Lease of Building Lease of building. Unconsolidated joint ventures, voting rights Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Interest Rate Swap Interest Rate Swap [Member] Common Stock Options and Grants Share-based Payment Arrangement [Policy Text Block] Name of Major Customer [Domain] Customer [Domain] Non-cash amortization of purchase accounting adjustments related to in-place leases Finite-Lived Intangible Asset, Acquired-in-Place Leases Additional paid-in capital Additional Paid in Capital, Common Stock 2021 Debt Securities, Available for Sale Securities Maturities, Year Two, at Par Debt Securities, Available for sale securities maturities, year two, at par. 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Segment Profits (Losses) Segment Reporting Information, Income (Loss) before Income Taxes [Abstract] Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-sale [Line Items] Document Transition Report Document Transition Report Cost of sales Cost of Purchased Water Net periodic pension benefit/(cost) Defined Benefit Plan, Expected Net Period Benefit Cost (Credit), Next Fiscal Year Defined Benefit Plan, Expected Net Period Benefit Cost (Credit), Next Fiscal Year Capitalization of costs Deferred Tax Assets, Deferred Expense, Capitalized Costs Deferred Tax Assets, Deferred Expense, Capitalized Costs Unrealized (loss) gain on available-for-sale securities OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, before Tax Other income (loss): Nonoperating Income (Expense) [Abstract] Prepaid expenses Deferred Tax Liabilities, Prepaid Expenses Face amount Additional bond debt authorized to be sold in future Debt Instrument, Face Amount Level 2 Fair Value, Inputs, Level 2 [Member] Option period purchase price Investment in Joint Venture Option Period Purchase Price Investment in Joint Venture Option Period Purchase Price Buildings and improvements Building and Building Improvements [Member] Cost components: Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] Rights offering, net Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs Maturities of Long-term Debt [Abstract] Maturities of Long-term Debt [Abstract] Farming Farming Farming and Agriculture [Member] Farming and agriculture. Weighted Average Interest Pay Rate Derivative, Fixed Interest Rate Tangible water assets Tangible Water Assets [Table Text Block] Tangible Water Assets [Table Text Block] Deferred income Contract with Customer, Liability, Current Other Liabilities Other Liabilities [Member] Customer concentration risk Customer Concentration Risk [Member] Repayments of line of credit Repayments of Short-term Debt Credit Facility [Domain] Credit Facility [Domain] Derivative Contract [Domain] Derivative Contract [Domain] Diluted shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Diluted Proceeds from sale of real estate/assets Proceeds from Sale of Real Estate Held-for-investment Litigation Case [Domain] Litigation Case [Domain] Net income (loss) per share attributable to common stockholders, basic (in dollars per share) Net Income (Loss) Per Share (in dollars per share) Earnings Per Share, Basic Environmental Expenditures Environmental Costs, Policy [Policy Text Block] Estimated taxes of change in value of available-for-sale securities OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, Tax Entity File Number Entity File Number Expired/forfeited grants (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Debt Disclosure [Abstract] Debt Disclosure [Abstract] Rate of increase in periodic pension costs Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase SERP liability adjustments Supplemental Employee Retirement Plan [Member] Acres of land Related Party Transaction, Area of Land Related Party Transaction, Area of Land Cash and Cash Equivalents Defined Benefit Plan, Cash and Cash Equivalents [Member] 2024 Lessor, Operating Lease, Payment to be Received, Year Four Accrued expenses Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities RLOC Revolving Line of Credit [Member] Revolving Line of Credit Net cash used in financing activities Net Cash Provided by (Used in) Financing Activities Repayments of long-term debt Repayments of Long-term Debt Revenues from External Customers and Long-Lived Assets [Line Items] Revenues from External Customers and Long-Lived Assets [Line Items] Total fair value of award Expensed Share-based Payment Arrangement, Expense Number of parties settled (more than) Loss Contingency, Number of Plaintiffs Balance Sheet Location [Axis] Balance Sheet Location [Axis] Tulare Lake Basin water rights Tulare Lake Basin Water Rights [Member] Tulare Lake Basin Water Rights [Member] Counterparty Name [Axis] Counterparty Name [Axis] Issued and outstanding shares - 26,276,830 at December 31, 2020 and 26,096,797 at December 31, 2019 Common Stock, Value, Issued 2024 Defined Benefit Plan, Expected Future Benefit Payment, Year Four Real estate - resort/residential Resort and Residential Real Estate [Member] Resort and Residential Real Estate Goodwill and Intangible Assets Disclosure [Abstract] Goodwill and Intangible Assets Disclosure [Abstract] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Document Fiscal Year Focus Document Fiscal Year Focus Actuarial (gain)/assumption changes Defined Benefit Plan, Actuarial Gain (Loss) and Other Changes Defined Benefit Plan, Actuarial Gain (Loss) and Other Changes Document Annual Report Document Annual Report Centennial Founders, LLC Centennial Centennial Founders LLC [Member] Centennial Founders LLC Property Subject to or Available for Operating Lease, by Major Property Class [Table] Property Subject to or Available for Operating Lease, by Major Property Class [Table] Commitment and Contingencies Disclosure [Line Items] Commitment and Contingencies Disclosure [Line Items] Commitment and contingencies disclosure. Commitments and Contingencies Disclosure [Table] Commitments and Contingencies Disclosure [Table] Commitments and contingencies disclosure. Current maturities of long-term debt Long-term Debt, Current Maturities Benefit obligation at beginning of year Benefit obligation and accumulated benefit obligation at end of year Defined Benefit Plan, Benefit Obligation Entity Current Reporting Status Entity Current Reporting Status Less: line-of-credit and current maturities of long-term debt Debt, Current West CFD West Community Facilities Districts [Member] West community facilities districts. Long-Term Water Assets Long Lived Assets Held for Sale or Future Use [Text Block] Long lived assets held for sale or future use. Net investment in water assets Net investments in water assets Long Term Assets Held for Future Use or Sale Long term assets held for future use or sale. 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Investing Activities Net Cash Provided by (Used in) Investing Activities [Abstract] Common stock, issued shares (in shares) Common Stock, Shares, Issued Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Less accumulated depreciation Inventory, Real Estate, Improvements, Accumulated Depreciation Inventory, Real Estate, Improvements, Accumulated Depreciation Revenue from External Customers by Products and Services [Table] Revenue from External Customers by Products and Services [Table] Other Deferred Tax Liabilities, Other Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Litigation Status [Axis] Litigation Status [Axis] Deferred Tax Liabilities, Net Deferred Tax Liabilities, Net Acre-Feet Sold Long Term Water Assets, Water Sold (Volume) Long Term Water Assets, Water Sold (Volume) Long-term debt, less current portion Long-term Debt, Excluding Current Maturities Segment Reporting [Abstract] Segment Reporting [Abstract] Debt Defined Benefit Plan, Debt Security [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Kern County Water Agency Kern County Water Agency [Member] Kern County Water Agency [Member] Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Total Tejon Ranch Co. Stockholders’ Equity Stockholders' Equity Attributable to Parent Receivables, inventories, prepaids and other assets, net Increase (Decrease) in Operating Assets Concentration Risk Type [Domain] Concentration Risk Type [Domain] Reimbursement proceeds from Communities Facilities District Payments for (Proceeds from) Other Investing Activities, Business Three Payments for (Proceeds from) Other Investing Activities, Business Three Area of land Area of Land TOTAL LIABILITIES AND EQUITY Liabilities and Equity Other Other Employee-related Liabilities, Current Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Income Taxes Income Tax Disclosure [Text Block] Fair Value Derivative Assets (Liabilities), at Fair Value, Net Entity Address, City or Town Entity Address, City or Town Notes payable Notes Payable Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Current liabilities, net Increase (Decrease) in Operating Liabilities Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Cash distribution received Proceeds from Real Estate and Real Estate Joint Ventures Water held for future use Long-term Water Assets, Banked Water and Water Contract Rights [Abstract] Long-term Water Assets, Banked Water and Water Contract Rights [Abstract] Tejon-Castac Water District Tejon-Castac Water District [Member] Tejon-Castac Water District [Member] Schedule of interest rate derivatives Schedule of Interest Rate Derivatives [Table Text Block] Total Stockholders' Equity Parent [Member] Deferred income tax liabilities: Deferred Tax Liabilities, Gross [Abstract] Financial Instrument [Axis] Financial Instrument [Axis] Reduction of noncontrolling interest in joint venture Noncontrolling Interest in Joint Ventures Equity Component [Domain] Equity Component [Domain] Number of types of awards Share Based Compensation Arrangement by Share Based Payment Award, Number of Award Types Share Based Compensation Arrangement by Share Based Payment Award, Number of Award Types Balance Sheet Information Equity Method Investment, Summarized Financial Information [Abstract] Equity Method Investment, Nonconsolidated Investee [Axis] Equity Method Investment, Nonconsolidated Investee [Axis] Allowance for deferred tax assets Deferred Tax Assets, Valuation Allowance Schedule of expected annual benefit payments Schedule of Expected Benefit Payments [Table Text Block] Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Centennial redemption of withdrawing member interest Adjustments to Additional Paid in Capital, Stock Issued, Modified Share-based Awards Adjustments to Additional Paid in Capital, Stock Issued, Modified Share-based Awards Earnings(Loss) Earnings (loss) Gross Profit Real Estate Real Estate Disclosure [Text Block] Property and equipment, net Property and equipment, net Net book value related to vineyards and other farming related assets Property, Plant and Equipment, Net Development in process Construction in Progress [Member] Entity Tax Identification Number Entity Tax Identification Number Revenue Recognition Revenue from Contract with Customer [Policy Text Block] Borrowings under joint venture Equity Method Investment Summarized Financial Information, Line of Credit Facility, Maximum Borrowing Capacity Equity Method Investment Summarized Financial Information, Line of Credit Facility, Maximum Borrowing Capacity Contract renewal optional term Long Term Water Assets, Contract Renewal Optional Term Long Term Water Assets, Contract Renewal Optional Term Net (loss) income attributable to common stockholders Net Income (Loss) attributable to Common Stockholders Net Income (Loss) Attributable to Parent Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Capital Expenditures Capital Expenditures Capital Expenditures Provision for additional capitalized costs Deferred Tax Assets, Deferred Expense, Provision for Additional Capitalized Costs Deferred Tax Assets, Deferred Expense, Provision for Additional Capitalized Costs Inventories Inventory Disclosure [Text Block] Investment, Name [Domain] Investment, Name [Domain] Other comprehensive (loss) income Other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax Annual option payment, percent Long Term Water Assets, Purchased, Annual Option Payment, Percent Long Term Water Assets, Purchased, Annual Option Payment, Percent Leases [Abstract] Leases [Abstract] Long Lived Assets Held-for-sale by Asset Type [Axis] Long Lived Assets Held-for-sale by Asset Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Total current assets Assets, Current Current Fiscal Year End Date Current Fiscal Year End Date Components of net deferred tax assets and liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Profit Gross Profit from Purchased Water Gross Profit from Purchased Water Number of community facility districts Number of Community Facility Districts Number of Community Facility Districts Tejon Ranch Co. Stockholders’ Equity Stockholders' Equity Attributable to Parent [Abstract] Document Fiscal Period Focus Document Fiscal Period Focus Restricted stock issuance Stock Issued During Period, Value, Restricted Stock Award, Gross Certificates of deposit Certificates of Deposit [Member] Non-cash write-off of leasing assets Non-Cash Write-off of Tenant Receivables Non-Cash Write-off of Tenant Receivables Long-term deferred gains Contract with Customer, Liability, Noncurrent Employer contribution Defined Benefit Plan, Plan Assets, Contributions by Employer Equity Method Investment, Nonconsolidated Investee or Group of Investees Equity Method Investment, Nonconsolidated Investee or Group of Investees [Member] Non-cash investing activities Supplemental Cash Flow Information [Abstract] Commercial lease agreements, contract terms Lessor, Operating Lease, Term of Contract Other Other Sundry Liabilities, Noncurrent Entity Filer Category Entity Filer Category Common Stock Common Stock [Member] Product and Service [Domain] Product and Service [Domain] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Property, Plant and Equipment, Type [Domain] Long-Lived Tangible Asset [Domain] 2020 Debt Securities, Available for Sale Securities Maturities Year One at Par Debt Securities, Available for sale securities maturities, year one, at par. Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Distribution of equity from unconsolidated joint ventures Proceeds from Equity Method Investment, Distribution, Return of Capital Benefits paid Defined Benefit Plan, Benefit Obligation, Benefits Paid Share price at target achievement (in dollars per share) Share based Compensation Arrangement by Share based Payment Award Price at Target Achievement Share based Compensation Arrangement by Share based Payment Award Price at Target Achievement Schedule of other changes in plan assets and benefit obligations recognized in other comprehensive income Schedule of Defined Benefit Plan Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block] Property and equipment and their respective useful lives Property, Plant and Equipment [Table Text Block] 2021 Lessor, Operating Lease, Payment to be Received, Year One Summary of income from commercial rents included in real estate revenue: Operating Leases, Income Statement, Lease Revenue [Abstract] Benefit (provision) for income taxes related to other comprehensive income items Other Comprehensive Income (Loss), Tax Costs Finite-Lived Intangible Assets, Gross Total Revenue Revenue and Nonoperating Income Revenue and Nonoperating Income Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Total amount recorded Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax Stated Rate Debt Instrument, Interest Rate, Stated Percentage with unrecognized losses for less than 12 months Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Acres of vineyards abandoned Acres of Abandoned Vineyards Acres of Abandoned Vineyards Money market funds Money Market Funds [Member] Municipal notes Municipal Bonds [Member] Less: accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Name of Property [Axis] Name of Property [Axis] Net actuarial loss Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Gain (Loss), before Tax Amounts recorded in stockholders’ equity Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax [Abstract] Related Party Transactions [Abstract] Related Party Transactions [Abstract] Increase (decrease) in cash and cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Total other income (loss) Nonoperating Income (Expense) Summary of stock grant activity Schedule of Nonvested Share Activity [Table Text Block] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Reportable Segment Segment Profit (Loss) [Member] Segment Profit (Loss) [Member] Difference between total income tax expense and the amount computed by applying the statutory Federal income tax rate to income before taxes: Effective Income Tax Rate Reconciliation, Amount [Abstract] Other Effective Income Tax Rate Reconciliation, Other Adjustments, Amount Common stock (in shares) Weighted Average Number of Shares Outstanding, Basic Basis spread on variable rate Debt Instrument, Basis Spread on Variable Rate Costs and expenses: Costs and Expenses [Abstract] Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Investments in unconsolidated joint ventures Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures Ownership [Axis] Ownership [Axis] Nickel water rights Nickel Water Rights [Member] Nickel Water Rights [Member] Variable Interest Entity Consolidation, Variable Interest Entity, Policy [Policy Text Block] Deferred Deferred State and Local Income Tax Expense (Benefit) Ownership [Domain] Ownership [Domain] 2025 Long-Term Debt, Maturity, Year Five Cost Reported Value Measurement [Member] 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 Plan Name [Domain] Plan Name [Domain] Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Ownership percentage Equity Method Investment, Ownership Percentage Rent billings percentage retained Rent Billings Percentage Retained Rent Billings Percentage Retained Borrowings Equity Method Investment Summarized Financial Information, Borrowings Equity Method Investment Summarized Financial Information, Borrowings Total equity Beginning balance, value Ending balance, value Equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Recognition of net actuarial gain or (loss) Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax Acres of land transferred Acres of Land Transferred Acres of Land Transferred Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Total revenues Revenues Commercial revenues Revenues Farm Inventories Inventory, Policy [Policy Text Block] Income tax expense Provision (benefit) for income taxes Income Tax Expense (Benefit) Expected return on plan assets Defined Benefit Plan, Expected Return on Plan Assets, Next Fiscal Year Defined Benefit Plan, Expected Return on Plan Assets, Next Fiscal Year Cash and cash equivalents at beginning of year Cash and cash equivalents at end of year Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Property and Equipment Property, Plant and Equipment, Policy [Policy Text Block] Summary of outstanding indebtedness and respective principal maturities Schedule of Maturities of Long-term Debt [Table Text Block] Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-sale [Table] Purchase of marketable securities Payments to Acquire Marketable Securities Net income (loss) per share attributable to common stockholders, diluted (in dollars per share) Net Income (Loss), Per Share attributable to Common Stockholders (in dollars per share) Earnings Per Share, Diluted Long term deferred profit on land contribution Deferred Gain On Contribution Of Land Deferred Gain On Contribution Of Land Local Phone Number Local Phone Number Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract] Components of debt Schedule of Debt [Table Text Block] December 12 2019 December 12 2019 [Member] December 12 2019 Tejon Ranch Commerce Center Tejon Ranch Commerce Center [Member] Tejon Ranch Commerce Center [Member] Liabilities for environmental costs Accrual for Environmental Loss Contingencies Quarterly Financial Information [Table] Quarterly Financial Information [Table] Quarterly Financial Information [Table] Investment income Investment Income, Net U.S. Treasury and agency notes US Treasury and Government Short-term Debt Securities [Member] Entity Address, Address Line One Entity Address, Address Line One Related Party Transaction [Domain] Related Party Transaction [Domain] Entity Emerging Growth Company Entity Emerging Growth Company Summary 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 Accrued paid personal leave Accrued Paid Personal Leave, Current Accrued Paid Personal Leave, Current Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Antelope Valley Groundwater Cases Antelope Valley Groundwater Cases [Member] Antelope Valley Groundwater Cases [Member] Book deferred gains Deferred Tax Assets, Book Deferred Gains Deferred Tax Assets, Book Deferred Gains Interest rate swap liability Derivative Liability, Fair Value, Gross Liability Accrued investment receivable Accrued Investment Income Receivable Assumptions used in determining periodic pension cost: Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract] Award Type [Axis] Award Type [Axis] Accumulated Depreciation Finite-Lived Intangible Assets, Accumulated Amortization Real estate and improvements - held for lease, net Real estate and improvements - held for lease, net Inventory, Real Estate, Improvements Maximum Maximum [Member] Property Subject to or Available for Operating Lease [Line Items] Property Subject to or Available for Operating Lease [Line Items] Noncontrolling Interest Noncontrolling Interest [Member] Stock grant expense Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Purchased water contracts Long-term Water Assets, Water Contracts (Volume) Long-term Water Assets, Water Contracts (Volume) Water assets, volume available for purchase from 2017-2030 (up to) (in acre-feet) Long-term Water Assets (Volume), Amount After Year One Long-term Water Assets (Volume), Amount After Year One Retained Earnings Retained Earnings [Member] Rockefeller Joint Ventures Rockefeller Joint Ventures [Member] Rockefeller joint ventures. Measurement Basis [Axis] Measurement Basis [Axis] Unrealized interest rate swap (loss) gain Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, before Tax Components of net periodic pension cost Schedule of Net Benefit Costs [Table Text Block] Effective tax rate Effective Income Tax Rate Reconciliation, Percent Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Net cash provided by/(used) in investing activities Net Cash Provided by (Used in) Investing Activities 2023 Lessor, Operating Lease, Payment to be Received, Year Three NDSI Plan Non-Employee Director Stock Incentive Plan [Member] Non-employee director stock incentive plan. Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of future minimum rental income Lessor, Operating Lease, Payment to be Received, Fiscal Year Maturity [Table Text Block] Award Type [Domain] Award Type [Domain] Summary of income from commercial rents included in real estate revenue Schedule of Rent Income [Table Text Block] Schedule of Rent Income [Table Text Block] Trading Symbol Trading Symbol Transferable water Long-term Water Assets, Transferrable Water (Volume) Long-term Water Assets, Transferrable Water (Volume) Non-deductible compensation Income Tax Reconciliation, Nondeductible Expense, Compensation Income Tax Reconciliation, Nondeductible Expense, Compensation Estimated future minimum annual payments Other Commitment Litigation Status [Domain] Litigation Status [Domain] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Total purchased water contracts Long-term Water Assets, Intangible Water Contracts (Volume) Long-term Water Assets, Intangible Water Contracts (Volume) Pension liability Pension plan Pension Plan [Member] Weighted-average discount rate Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Oil and mineral depletion Effective Income Tax Rate Reconciliation, Nondeductible Expense, Depletion, Amount Current Liabilities: Liabilities, Current [Abstract] Entity Shell Company Entity Shell Company Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Shares withheld for taxes and tax benefit of vested shares (in shares) Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Entity Public Float Entity Public Float Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Percentage of rentable space occupied Joint Venture, Percentage of Rentable Space Occupied Joint Venture, Percentage of Rentable Space Occupied Number of joint venture contracts Number of Joint Venture Contracts Number of joint venture contracts.