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)

v3.23.3

Stock-Based Compensation - Stock Option Activity (Details) - USD ($)	6 Months Ended	9 Months Ended	12 Months Ended
	Jun. 30, 2021	Sep. 30, 2023	Dec. 31, 2022
Exercise Price Per Share [Abstract]
Exercise Price Per Share, Outstanding, Minimum (per share)		$ 1.10	$ 0.71
Exercise Price Per Share, Outstanding, Maximum (dollars per share)		3.20	$ 10.33
Exercise price per share, Vested and expected to vest (dollars per share)		0.71
Minimum
Exercise Price Per Share [Abstract]
Exercise price per share, Granted (dollars per share)		0.88
Maximum
Exercise Price Per Share [Abstract]
Exercise price per share, Granted (dollars per share)		$ 1.10
Tecogen
Stock Options Outstanding [Roll Forward]
Beginning (shares)		3,204,297
Granted (shares)		575,000
Exercised (shares)		0
Canceled and forfeited (shares)		(44,800)
Ending (shares)		3,734,497	3,204,297
Exercisable (shares)		1,931,322
Vested and expected to vest (shares)		3,462,521
Weighted Average Exercise Price [Roll Forward]
Beginning (usd per share)		$ 1.61
Granted (usd per share)		0.93
Canceled and forfeited (usd per share)		2.86
Ending (usd per share)		1.49	$ 1.61
Exercisable (usd per share)		1.97
Vested and expected to vest (usd per share)		$ 1.53
Weighted Average Remaining Life	7 years 3 months 18 days	7 years 1 month 20 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Outstanding, Aggregate Intrinsic Value		$ 188,529	$ 882,074
Exercisable, Aggregate Intrinsic Value		112,578
Vested and expected to vest, Aggregate Intrinsic Value		$ 177,136

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Cancellations and Forfeitures in 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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Gross number of share options (or share units) granted during the period.

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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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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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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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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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