Quarterly report pursuant to Section 13 or 15(d)

Cover
- Cover
Financial Statements
Notes to Financial Statements
Accounting Policies
- Description of business and basis of presentation (Policies)
Notes Tables
Notes Details

Stock-Based Compensation - Stock Option Activity (Details)

v3.24.1.u1

Stock-Based Compensation - Stock Option Activity (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Exercise Price Per Share [Abstract]
Exercise Price Per Share, Outstanding, Minimum (per share)	$ 0.71	$ 0.71
Exercise Price Per Share, Outstanding, Maximum (dollars per share)	6.74
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Share Based Compensation Shares Authorized Under Stock Option Plans, Granted, Exercise Price Range, Upper Range Limit		$ 10.33
Share Based Compensation Shares Authorized Under Stock Option Plans, Cancelled and Forfeited, Exercise Price Range, Lower Range Limit	0.74
Share Based Compensation Shares Authorized Under Stock Option Plans, Cancelled and Forfeited, Exercise Price Range, Upper Range Limit	$ 10.33
Tecogen
Stock Options Outstanding [Roll Forward]
Beginning (shares)	3,638,122
Canceled and forfeited (shares)	(801,350)
Ending (shares)	2,836,772	3,638,122
Exercisable (shares)	1,643,022
Vested and expected to vest (shares)	2,657,710
Weighted Average Exercise Price [Roll Forward]
Beginning (usd per share)	$ 1.49
Canceled and forfeited (usd per share)	2.73
Ending (usd per share)	1.14	$ 1.49
Exercisable (usd per share)	1.28
Vested and expected to vest (usd per share)	$ 1.16
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Outstanding, Aggregate Intrinsic Value		$ 127,811
Vested and expected to vest, Aggregate Intrinsic Value	$ 0
Tecogen \| Stock Options
Weighted Average Exercise Price [Roll Forward]
Weighted Average Remaining Life	7 years 21 days	6 years 8 months 12 days

- Definition

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Cancellations and Forfeitures in Period

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Cancellations and Forfeitures in Period, Weighted Average Exercise Price

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- Definition

Lower range of Exercise price per share of stock options cancelled and forfeited during the period.

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Upper range of Exercise price per share of stock options cancelled and forfeited during the period.

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Upper range of Exercise price per share of stock options granted during the period.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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