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v3.23.3

Note 1 - Nature of Activities and Summary of Significant Accounting Policies (Details Textual) $ in Thousands, gal in Millions | 1 Months Ended | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
May 31, 2022 USD ($) | Oct. 31, 2020 USD ($) | Mar. 31, 2023 USD ($) gal | Dec. 31, 2022 USD ($) | Jun. 30, 2023 USD ($) | Sep. 30, 2023 USD ($) MMBTU | Dec. 31, 2022 USD ($)
Renewable Natural Gas in Storage (Millions of British Thermal Unit) | MMBTU |  |  |  |  |  | 64,690 |
Other Receivable [Member] |  |  |  |  |  |  |
Accumulated Deferred Investment Tax Credit |  |  |  |  |  | $ 55,200 |
U.S. Department of Food And Agriculture Forest Service [Member] |  |  |  |  |  |  |
Awarded Grants |  |  |  |  | $ 245 |  |
Proceeds from Grantors |  |  |  |  | 245 |  |
LCFPP [Member] |  |  |  |  |  |  |
Awarded Grants |  |  |  |  |  | 4,200 |
Proceeds from Grantors |  |  |  |  |  | 3,800 |
CDFAs[Member] |  |  |  |  |  |  |
Awarded Grants |  | $ 7,800 |  |  |  |  |
Proceeds from Grantors |  |  |  |  |  | $ 4,800 |
CEC [Member] |  |  |  |  |  |  |
Awarded Grants |  |  |  |  | 8,000 |  |
Proceeds from Grantors |  |  |  |  | 4,200 |  |
Unearned Grant Proceeds |  |  |  |  | 1,700 |  | $ 1,700
Matching Contribution |  |  |  |  | 1,600 |  |
CEC [Member] | Maximum [Member] |  |  |  |  |  |  |
Awarded Grants |  |  |  |  | 5,000 |  |
CAL FIRE Business and Workforce Development Grant Program [Member] |  |  |  |  |  |  |
Awarded Grants | $ 2,000 |  |  |  |  |  |
Proceeds from Grantors |  |  |  |  |  |  | 0
Matching Contribution | 5,800 |  |  |  |  |  |
CAL Fire [Member] |  |  |  |  |  |  |
Awarded Grants | 500 |  |  |  |  |  |
Proceeds from Grantors |  |  |  |  |  |  | $ 0
US Forest Service [Member] |  |  |  |  |  |  |
Awarded Grants | 642 |  |  |  |  |  |
Matching Contribution | $ 2,400 |  |  |  |  |  |
AAFK Plan [Member] |  |  |  |  |  |  |
Awarded Grants |  |  |  |  | 6,000 |  |
Matching Contribution |  |  |  |  | 5,300 |  |
PG&E SEM Incentive Program [Member] |  |  |  |  |  |  |
Proceeds from Grantors |  |  |  | $ 374 | $ 27 |  |
CEC PG&E Pipeline Interconnect [Member] |  |  |  |  |  |  |
Proceeds from Grantors |  |  | $ 5,000 |  |  |  |
Kakinada Plant [Member] |  |  |  |  |  |  |
GallonPerYear (Gallon) | gal |  |  | 50 |  |  |  |

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