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)

v3.23.2

Stock-Based Compensation - Stock Option Activity (Details) - Tecogen - USD ($)	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2021	Jun. 30, 2023	Dec. 31, 2022
Stock Options Outstanding [Roll Forward]
Beginning (shares)	3,204,297		3,204,297
Granted (shares)			125,000
Exercised (shares)			0
Canceled and forfeited (shares)			(42,000)
Ending (shares)			3,287,297
Exercisable (shares)			1,788,972
Vested and expected to vest (shares)			3,062,548
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)	10.33		10.33
Weighted Average Exercise Price [Roll Forward]
Beginning (usd per share)	$ 1.61		1.61
Granted (usd per share)			1.11
Canceled and forfeited (usd per share)			2.98
Ending (usd per share)			1.57
Exercisable (usd per share)			2.06
Vested and expected to vest (usd per share)			$ 1.61
Weighted Average Remaining Life		7 years 3 months 18 days	7 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Outstanding, Aggregate Intrinsic Value			$ 406,845	$ 882,074
Exercisable, Aggregate Intrinsic Value			206,145
Vested and expected to vest, Aggregate Intrinsic Value			$ 376,740
Minimum
Exercise Price Per Share [Abstract]
Exercise price per share, Granted (dollars per share)			$ 1.10

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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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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 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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Number of share options (or share units) exercised during the current period.

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