Payment term on energy production contract invoices Payment Term on Energy Production Contract Invoices Payment Term on Energy Production Contract Invoices Unrealized loss on investment securities Unrealized loss on investment securities Unrealized Gain (Loss) on Investments Less - accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Statistical Measurement [Domain] Statistical Measurement [Domain] Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] Award Timing Predetermined Award Timing Predetermined [Flag] Related Party Transaction [Axis] Related Party Transaction [Axis] Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Intangible assets Intangible Assets, Gross (Excluding Goodwill) Indefinite-lived Intangible Assets [Axis] Indefinite-Lived Intangible Assets [Axis] Asset Class [Axis] Asset Class [Axis] Finite-Lived Intangible Assets, Net, Amortization Expense, Rolling Maturity [Abstract] Finite-Lived Intangible Assets, Net, Amortization Expense, Rolling Maturity [Abstract] Entity File Number Entity File Number Additional Paid-In Capital Additional Paid-in Capital [Member] Revenue billed this period that had been recognized in previous periods Contract with Customer, Performance Obligation Satisfied in Previous Period Tabular List, Table Tabular List [Table Text Block] Leases [Abstract] Leases [Abstract] July 2024 Promissory Note July 2024 Promissory Note [Member] July 2024 Promissory Note Number of Assets Acquired Number of Assets Acquired Number of Assets Acquired Contingent consideration, percentage Asset Acquisition, Contingent Consideration, Percentage Asset Acquisition, Contingent Consideration, Percentage Significant Accounting Standards Adopted in the Period and Recently Issued Accounting Standards New Accounting Pronouncements, Policy [Policy Text Block] Maintenance Services [Member] Maintenance Services [Member] Maintenance Services [Member] Accounts payable Increase (Decrease) in Accounts Payable Deferred revenue, net of current portion Deferred Revenue, Noncurrent Unbilled revenue Contract with Customer, Asset, after Allowance for Credit Loss, Current Earl R. Lewis, III Earl R. Lewis, III [Member] Earl R. Lewis, III Ownerhsip interest in American DG New York, LLC (percent) Percentage Of Owned Joint Venture Percentage Of Owned Joint Venture. Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Measurement Basis [Axis] Measurement Basis [Axis] Net income (loss) per share - basic (in USD per share) Earnings Per Share, Basic Adjustment to Compensation: Adjustment to Compensation [Axis] Energy Production [Member] Energy Production [Member] Energy Production [Member] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Shares of common stock reserved for future issuance (in shares) Common Stock, Capital Shares Reserved for Future Issuance Lessee, Operating Lease, Liability, to be Paid, after Year Four Lessee, Operating Lease, Liability, to be Paid, after Year Four Lessee, Operating Lease, Liability, to be Paid, after Year Four Revenue Revenue from Contract with Customer [Text Block] Subsidiary or Equity Method Investee, Sale of Stock, Type [Table] Subsidiary or Equity Method Investee, Sale of Stock, Type [Table] Measurement Input, Discount Rate Measurement Input, Discount Rate [Member] Fair value of options issued Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Grants In Period, Fair Value Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Grants In Period, Fair Value Schedule of Segment Reporting Information Schedule of Segment Reporting Information, by Segment [Table Text Block] Year 4 Finite-Lived Intangible Assets, Amortization Expense, Rolling Year Four Inventory Disclosure [Abstract] Construction in progress costs Construction In Progress Expenditures Construction In Progress Expenditures Remaining performance obligations Revenue, Remaining Performance Obligation, Amount Measurement Input Type [Domain] Measurement Input Type [Domain] Adjustment to Compensation, Amount Adjustment to Compensation Amount Option to extend lease, monthly rent Lessee, Operating Lease, Option To Extend, Monthly Rent Lessee, Operating Lease, Option To Extend, Monthly Rent American DG Energy, Inc. American DG Energy [Member] American DG Energy [Member] Revenue, remaining performance obligation, percentage Revenue, Remaining Performance Obligation, Percentage Other assets Increase (Decrease) in Other Operating Assets Stock-based compensation Share-Based Payment Arrangement, Noncash Expense Finance Lease, Liability, to be Paid, Year Three Finance Lease, Liability, to be Paid, Year Three Exercise price per share, exercised, lower range limit (in dollars per share) Share-Based Payment Arrangement, Option, Exercise Price Range, Exercises In Period, Lower Range Limit Share-Based Payment Arrangement, Option, Exercise Price Range, Exercises In Period, Lower Range Limit Stock Options Share-Based Payment Arrangement, Option [Member] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Consideration received Proceeds from Sale of Productive Assets Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Contingent Consideration, Noncurrent Contingent Consideration, Noncurrent [Member] Contingent Consideration, Noncurrent Cash paid for taxes Income Taxes Paid Assets and Liabilities, Lessee Assets and Liabilities, Lessee [Table Text Block] Assets and Liabilities, Lessee Antidilutive Securities [Axis] Antidilutive Securities [Axis] Total Tecogen Inc. stockholders’ equity Equity, Attributable to Parent Measurement Frequency [Axis] Measurement Frequency [Axis] Insider Trading Policies and Procedures [Line Items] Share-Based Payment Arrangement, Expense Share-Based Payment Arrangement, Expense Summary of Property, Plant and Equipment Property, Plant and Equipment [Table Text Block] Common stock, shares authorized Common Stock, Shares Authorized Goodwill and Intangible Assets Disclosure [Abstract] Goodwill and Intangible Assets Disclosure [Abstract] Patents Patents [Member] Current assets: Assets, Current [Abstract] Cash paid for amounts included in the measurement of finance lease liabilities Finance Lease, Principal Payments And Other Costs Finance Lease, Principal Payments And Other Costs TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY Liabilities and Equity Number of sales of energy producing assets Number of Sales of Energy Producing Assets Number of Sales of Energy Producing Assets Other liabilities Increase (Decrease) in Other Current Liabilities Fair Value, Measurements, Recurring Fair Value, Recurring [Member] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Stock Options Outstanding [Roll Forward] Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding [Roll Forward] Operating lease, improvements Lessee, Operating Lease, Improvements Lessee, Operating Lease, Improvements LIABILITIES AND STOCKHOLDERS’ EQUITY Liabilities and Equity [Abstract] Portion at Fair Value Measurement [Member] Portion at Fair Value Measurement [Member] Sale of Energy Producing Assets Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Maximum Maximum [Member] Exercisable (usd per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price Finite lived intangible assets, estimated useful life Finite-Lived Intangible Asset, Useful Life (Income) loss attributable to the noncontrolling interest Net Income (Loss) Attributable to Noncontrolling Interest Accounting Policies [Abstract] Accounting Policies [Abstract] Asset Acquisition, Assets Acquired and Liabilities Assumed, Net Asset Acquisition, Assets Acquired and Liabilities Assumed, Net Asset Acquisition, Assets Acquired and Liabilities Assumed, Net Historical forfeiture rate Share Based Compensation Arrangement by Share Based Payment Award, Historical Forfeiture Rate Share Based Compensation Arrangement by Share Based Payment Award, Historical Forfeiture Rate Property and equipment, net, before construction in progress Property, Plant And Equipment, Net, Before Public Utilities, Contruction Work In Progress Property, Plant And Equipment, Net, Before Public Utilities Contruction Work In Progress Intangible assets, net Total Finite-Lived Intangible Assets, Net Future Minimum Lease Commitments Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block] Restricted Stock Restricted Stock [Member] Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Canceled and forfeited (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Cancellations and Forfeitures in Period Share-based Compensation Arrangement by Share-based Payment Award, Options, Cancellations and Forfeitures in Period Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Pay vs Performance Disclosure [Line Items] Total operating lease liability Operating Lease, Liability Operating Lease, Liability Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Finite-Lived Intangible Liability [Domain] Finite-Lived Intangible Liability [Domain] Finite-Lived Intangible Liability [Domain] Aegis Contract and Related Asset Acquisitions Business Combination [Text Block] Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Depreciation of right-of-use assets Finance Lease, Right-of-Use Asset, Amortization Loss before provision for state income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Entity Shell Company Entity Shell Company Asset Acquisition, Consideration Transferred, Contingent Consideration, Current Asset Acquisition, Consideration Transferred, Contingent Consideration, Current Asset Acquisition, Consideration Transferred, Contingent Consideration, Current Total finance lease cost Finance Lease, Cost Finance Lease, Cost Deferred revenue Increase (Decrease) in Deferred Revenue Exercise price per share, granted (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Granted in Period, Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Granted in Period, Exercise Price Operating leases Operating Lease, Assets And Liabilities, Lessee [Abstract] Operating Lease, Assets And Liabilities, Lessee Original listing fee Payment For Original Listing Fee Payment For Original Listing Fee Exercise Price Per Share, Outstanding, Maximum (in dollars per share) Share-Based Payment Arrangement, Option, Exercise Price Range, Upper Range Limit Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Operating Segments Operating Segments [Member] Remaining lease term Lessee, Operating Lease, Remaining Lease Term Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Company Selected Measure Amount Company Selected Measure Amount Lessee, Operating Lease, Liability, to be Paid, Year Three Lessee, Operating Lease, Liability, to be Paid, Year Three Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Operating and Finance Lease, Liability, to be Paid Operating and Finance Lease, Liability, to be Paid Operating and Finance Lease, Liability, to be Paid Measurement Input Type [Axis] Measurement Input Type [Axis] Other income (expense), net Interest and Other Income (Expense) Interest and Other Income (Expense) September 2024 Promissory Note September 2024 Promissory Note [Member] September 2024 Promissory Note Name Measure Name Key Employees Key Employees [Member] Key Employees Operating lease liability, current portion Operating lease liability, current portion Operating Lease, Liability, Current Interest on lease liabilities Finance Lease, Interest Expense Computer software Software and Software Development Costs [Member] Document Fiscal Period Focus Document Fiscal Period Focus Award Timing Method Award Timing Method [Text Block] Exercise price per share, exercised, upper range limit (in dollars per share) Share-Based Payment Arrangement, Option, Exercise Price Range, Exercises In Period, Upper Range Limit Share-Based Payment Arrangement, Option, Exercise Price Range, Exercises In Period, Upper Range Limit Furniture and Fixtures [Member] Furniture and Fixtures [Member] Award Type [Axis] Award Type [Axis] Unearned compensation Deferred Compensation Equity Operating and Finance Lease, Liability, to be Paid, Year Three Operating and Finance Lease, Liability, to be Paid, Year Three Operating and Finance Lease, Liability, to be Paid, Year Three Square feet of lease Lessee, Operating Lease, Square Feet Lessee, Operating Lease, Square Feet Tecogen Parent Company [Member] Number of vehicles under finance lease Number Of Vechicels Under Finance Lease Number Of Vechicels Under Finance Lease TOTAL ASSETS Identifiable assets Assets Trading Symbol Trading Symbol Asset Acquisition, Goodwill Asset Acquisition, Goodwill Asset Acquisition, Goodwill Lessee, Operating Lease, Liability, to be Paid, Year Four Lessee, Operating Lease, Liability, to be Paid, Year Four Business Combinations Business Combination [Policy Text Block] Payment term on contractually determined milestones Payment Term on Contractually Determined Milestones Payment Term on Contractually Determined Milestones Increase (Decrease) in Working Capital Increase (Decrease) in Working Capital Increase (Decrease) in Working Capital Income Taxes Income Tax, Policy [Policy Text Block] Finance leases Finance Lease, Assets And Liabilities, Lessee [Abstract] Finance Lease, Assets And Liabilities, Lessee Entity Address, City or Town Entity Address, City or Town CASH FLOWS FROM OPERATING ACTIVITIES: Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Weighted-average discount rate - finance leases Finance Lease, Weighted Average Discount Rate, Percent Year 1 Finite-Lived Intangible Assets And Liability, Net, Amortization Expense, Next Rolling 12 Months Finite-Lived Intangible Assets And Liability, Net, Amortization Expense, Next Rolling 12 Months Intangible Assets and Liabilities Other Than Goodwill Intangible Assets Disclosure [Text Block] Inventories, net Inventory Disclosure [Text Block] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Ownership interest (percent) Subsidiary or Equity Method Investee, Cumulative Percentage Ownership after All Transactions Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Entity Emerging Growth Company Entity Emerging Growth Company Finance Lease, Liability, to be Paid, Year One Finance Lease, Liability, to be Paid, Year One Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Legal fees Payment For Legal Fees Payment For Legal Fees Increase (Decrease) in Operating Assets [Abstract] Increase (Decrease) in Operating Assets [Abstract] Weighted-average remaining lease term - finance leases Finance Lease, Weighted Average Remaining Lease Term Right-of-use assets acquired under operating leases Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Beginning (shares) Ending (shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number 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] Unfavorable Contract Liability Unfavorable Contract Liability [Member] Unfavorable Contract Liability [Member] Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Business Combination [Domain] Business Combination [Domain] Intangible assets, measurement input Intangible Assets, Measurement Input Intangible Assets, Measurement Input John N. Hatsopoulos John N. Hatsopoulos [Member] John N. Hatsopoulos Related Party Related Party [Member] Finance Lease, Liability, Undiscounted Excess Amount Finance Lease, Liability, Undiscounted Excess Amount Common stock, shares outstanding Common Stock, Shares, Outstanding Provision for (recovery of) credit losses Accounts Receivable, Credit Loss Expense (Reversal) Unfavorable contract liability, current portion Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Liabilities, Current Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Liabilities, Current Plan Name [Axis] Plan Name [Axis] PEO PEO [Member] Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Average number of employees Entity Number of Employees Corporate, other and elimination Corporate Segment and Other Operating Segment [Member] Exercise of stock options Stock Issued During Period, Value, Stock Options Exercised 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] Vehicles Acquired Under Finance Leases Vehicles Acquired Under Finance Leases Vehicles Acquired Under Finance Leases Net credit to cost of sales for amortization of contract related intangible assets and liabilities Amortization of Contract Related Intangible Assets and Liabilities, Net Amortization of Contract Related Intangible Assets and Liabilities, Net Schedule of Future Amortization Expense Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Expected volatility Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate 2022 Stock Incentive Plan 2022 Stock Incentive Plan [Member] 2022 Stock Incentive Plan Working Capital, Net Working Capital, Net Working Capital, Net Accumulated Deficit Retained Earnings [Member] Prepaid and other current assets Prepaid Expense and Other Assets, Current Entity Address, Postal Zip Code Entity Address, Postal Zip Code Restatement Determination Date Restatement Determination Date Cash and cash equivalents, beginning of the period Cash and cash equivalents, end of the period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Income Statement [Abstract] Income Statement [Abstract] Number of Employees Acquired Number of Employees Acquired Number of Employees Acquired Percentage of excess cash flows above threshold Energy Production Agreements, Percentage Of Excess Cash Flows Above Threshold Energy Production Agreements, Percentage Of Excess Cash Flows Above Threshold Sale of Stock [Domain] Sale of Stock [Domain] Intangible assets, net Intangible Assets, Net (Excluding Goodwill) Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Average Closing Share Price Average Closing Share Price [Member] Average Closing Share Price Product and Service [Domain] Product and Service [Domain] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Property and equipment, gross Property, Plant and Equipment, Gross Asset Acquisition, Number Of Additional Maintenance Contracts Asset Acquisition, Number Of Additional Maintenance Contracts Asset Acquisition, Number Of Additional Maintenance Contracts Consolidated net loss Net (loss) income Consolidated net loss Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Total recurring fair value measurements Liabilities, Fair Value Disclosure Business Combination [Table] Business Combination [Table] Discontinued Operations and Disposal Groups [Abstract] Discontinued Operations and Disposal Groups [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Year 2 Finite-Lived Intangible Assets, Amortization Expense, Rolling Year Two Other income (expense), net Other Income and Expenses [Abstract] Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Goodwill, Acquired During Period Goodwill, Acquired During Period Proceeds from exercise of stock options Proceeds from Stock Options Exercised Aegis Energy Services, LLC Aegis Energy Services, LLC [Member] Aegis Energy Services, LLC 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] Asset Acquisition, Maintenance Agreements, Number Of Additional Cogeneration Units Asset Acquisition, Maintenance Agreements, Number Of Additional Cogeneration Units Asset Acquisition, Maintenance Agreements, Number Of Additional Cogeneration Units Unearned Compensation Deferred Compensation, Share-Based Payments [Member] Accrued expenses Accrued Liabilities, Current Business Combination, Consideration Transferred, Equity Interest [Table] Business Combination, Consideration Transferred, Equity Interest [Table] Energy Equipment [Member] Energy Equipment [Member] CASH FLOWS FROM INVESTING ACTIVITIES: Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] General and administrative General and Administrative Expense Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Net cash used in operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Related Party Transactions [Abstract] Related Party Transactions [Abstract] Useful life - years Property, Plant and Equipment, Useful Life Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Lease cost Lease, Cost Goodwill Goodwill Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Supplemental Information Related to Leases Lease, Cost [Table Text Block] PEO Total Compensation Amount PEO Total Compensation Amount Vested and expected to vest (usd per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price Finance Lease, Liability, to be Paid, Year Four Finance Lease, Liability, to be Paid, Year Four October 2023 And July 2024 Promissory Notes October 2023 And July 2024 Promissory Notes [Member] October 2023 And July 2024 Promissory Notes Equity Components [Axis] Equity Components [Axis] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Description of Business and Basis of Presentation Nature of Operations [Text Block] Minimum guaranteed cash flows Energy Production Agreements, Minimum Guaranteed Cash Flows Energy Production Agreements, Minimum Guaranteed Cash Flows Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Products Product [Member] Number of reportable segments Number of Reportable Segments Products Segment Products Segment [Member] Products Segment Supplemental disclosure of cash flow information: Supplemental Cash Flow Information [Abstract] Other Performance Measure, Amount Other Performance Measure, Amount Weighted Average Exercise Price [Roll Forward] Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Entity Address, State or Province Entity Address, State or Province Finance lease principal payments Finance Lease, Principal Payments Antidilutive Security, Excluded EPS Calculation [Table] Antidilutive Security, Excluded EPS Calculation [Table] Related-party note repayment Repayments Of Related Party Debt, Including Interest Repayments Of Related Party Debt, Including Interest Related and Nonrelated Parties [Domain] Related and Nonrelated Parties [Domain] Total current liabilities Liabilities, Current Over-Allotment Option Over-Allotment Option [Member] Number of buildings in lease agreements Lessee, Operating Lease, Number Of Buildings Lessee, Operating Lease, Number Of Buildings Individual: Individual [Axis] Right-of-use assets acquired under finance leases Right-of-Use Asset Obtained in Exchange for Finance Lease Liability Asset Acquisition, Property, Plant and Equipment Asset Acquisition, Property, Plant and Equipment Asset Acquisition, Property, Plant and Equipment Net cash provided by (used) in investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 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] Cash paid for interest Interest Paid, Excluding Capitalized Interest, Operating Activity Asset Acquisition, Inventory Asset Acquisition, Inventory Asset Acquisition, Inventory Document Fiscal Year Focus Document Fiscal Year Focus Year 4 Finite-Lived Intangible Assets And Liability, Net, Amortization Expense, Rolling Year Four Finite-Lived Intangible Assets And Liability, Net, Amortization Expense, Rolling Year Four Chiller Chiller [Member] Chiller Stock-Based Compensation Shareholders' Equity and Share-Based Payments [Text Block] Right-of-use assets - operating leases Operating Lease, Right-of-Use Asset Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Entity Interactive Data Current Entity Interactive Data Current Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract] Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract] Distributions to noncontrolling interest Payments to Noncontrolling Interests, Investing Activities Payments to Noncontrolling Interests, Investing Activities Plan Name [Domain] Plan Name [Domain] Decrease in gross receipts in quarter (percent) Decrease in Gross Receipts Decrease in Gross Receipts Compensation cost not yet recognized, period for recognition Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Exercise of stock options (shares) Exercised (shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period Stockholders’ equity: Equity [Abstract] Exercisable, Aggregate Intrinsic Value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Intrinsic Value Segments Segment Reporting Disclosure [Text Block] Cogeneration Cogeneration [Member] Cogeneration Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Number of lease agreements Lessee, Operating Lease, Number Of Lease Agreements Lessee, Operating Lease, Number Of Lease Agreements Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Trademarks Trademarks [Member] Property, Plant and Equipment, Type [Axis] Long-Lived Tangible Asset [Axis] 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] Payment term on product sales Payment Term on Product Sales Payment Term on Product Sales Boiler Boiler [Member] Boiler Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Finance Lease, Liability, to be Paid, Year Two Finance Lease, Liability, to be Paid, Year Two Amortization of intangible assets Amortization of Intangible Assets Depreciation and amortization Depreciation, Depletion and Amortization Other assets Other Assets, Noncurrent Exercise Price, Canceled and Forfeited (dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Cancelled and Forfeited in Period, Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Cancelled and Forfeited in Period, Exercise Price Entity Central Index Key Entity Central Index Key PEO Name PEO Name Net proceeds from stock offering Net offering proceeds Sale of Stock, Consideration Received on Transaction 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] Year 1 Finite-Lived Intangible Assets, Amortization Expense, Next Rolling 12 Months Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Operating and Finance Lease, Liability Operating and Finance Lease, Liability Operating and Finance Lease, Liability Option to extend, period Lessee, Operating Lease, Option To Extend, Period Lessee, Operating Lease, Option To Extend, Period Finance Lease, Liability Total finance lease liability Finance Lease, Liability Acquisition liabilities, net of current portion Business Combination, Contingent Consideration, Liability, Noncurrent Arrangement Duration Trading Arrangement Duration Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Deferred revenue recognized Deferred Revenue, Revenue Recognized Segments [Axis] Segments [Axis] Inventory, Work in Process, Net of Reserves Inventory, Work in Process, Net of Reserves Exercise Price Award Exercise Price Fair Value by Liability Class [Domain] Fair Value by Liability Class [Domain] Entity Filer Category Entity Filer Category Local Phone Number Local Phone Number Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Contingent consideration Asset Acquisition, Consideration Transferred, Non-Cash, Contingent Consideration Asset Acquisition, Consideration Transferred, Non-Cash, Contingent Consideration Engineered Accessories Engineered Accessories [Member] Engineered Accessories Acquisition liabilities, current portion Business Combination, Contingent Consideration, Liability, Current Thereafter Finite-Lived Intangible Assets, Amortization Expense, Rolling after Year Five ASSETS Assets [Abstract] Share Based Compensation Shares Authorized Under Stock Option Plans, Cancelled and Forfeited, Exercise Price Range, Lower Range Limit Share Based Compensation Shares Authorized Under Stock Option Plans, Cancelled and Forfeited, Exercise Price Range, Lower Range Limit Lower range of Exercise price per share of stock options cancelled and forfeited during the period. Underlying Security Market Price Change Underlying Security Market Price Change, Percent Public Stock Offering Public Stock Offering [Member] Public Stock Offering Fair Value Measurements Fair Value Disclosures [Text Block] Business Combination [Line Items] Business Combination [Line Items] Tecogen Inc. shareholders’ 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 Principles of Consolidation and Basis of Presentation Principles Of Consolidation and Basis Of Presentation [Policy Text Block] Disclosure of accounting policy for principles of consolidation and basis of presentation. Research and development Research and Development Expense Accounts receivable, allowance for credit losses Accounts Receivable, Allowance for Credit Loss, Current Related party transaction, period Related Party Transaction, Period Related Party Transaction, Period Operating lease liability, net of current portion Operating Lease, Liability, Noncurrent Conversion of convertible securities (in shares) Stock Issued During Period, Shares, Conversion of Convertible Securities Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract] Payment period Revenue From Contract With Customer, Payment Period Revenue From Contract With Customer, Payment Period Asset Acquisition, Consideration Transferred, Accounts Payable Asset Acquisition, Consideration Transferred, Accounts Payable Asset Acquisition, Consideration Transferred, Accounts Payable Exercise Price Per Share, Outstanding, Minimum (in dollars per share) Share-Based 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