Note 12 - Subsequent Events	6 Months Ended
Jun. 30, 2021
Notes to Financial Statements
Subsequent Events [Text Block]	NOTE 12 — SUBSEQUENT EVENTS Cash Dividend On August 4, 2021, the Board of Directors of the Company declared, approved and authorized payment of a quarterly dividend of $6.7 million ($0.12 per share) to all holders of the Company’s issued and outstanding shares of common stock on August 18, 2021, payable on September 1, 2021. Geothermal assets purchase transaction On July 14, 2021, the Company closed a transaction with TG Geothermal Portfolio, LLC (a subsidiary of Terra-Gen, LLC) to acquire two contracted geothermal assets in Nevada with a total net generating capacity of 67.5 MW, a greenfield development asset adjacent to one of the plants, and an underutilized transmission line. The Company paid approximately $171 million (excluding working capital and assumed cash, which are subject to final audit) for 100% of the equity interests and assumed debt and associated lease obligations with a book value of approximately $206 million as of June 30, 2021. The two contracted geothermal assets include the Dixie Valley and Beowawe geothermal power plants which sell power under existing power purchase agreements with Southern California Edison under a long term PPA expiring in 2038 and with NV Power, Inc. under a PPA expiring in December 2025, respectively. The Company will account for the transaction under ASC 805, Business Combinations and is currently evaluating the accounting related to the transaction. The Company expects to consolidate acquired assets in its consolidated financial statements starting at the acquisition date. Hapoalim loan On July 12, 2021, the Company entered into a definitive loan agreement (the "Hapoalim Loan Agreement") with Bank Hapoalim B.M. (the “Bank Hapoalim”). The Hapoalim Loan Agreement provides for a loan by Bank Hapoalim to the Company in an aggregate principal amount of $125 million (the “Hapoalim Loan”). The outstanding principal amount of the Hapoalim Loan will be repaid in 14 semi-annual payments of $8.9 million each, commencing on December 12, 2021. The duration of the Hapoalim Loan is 7 years. The Hapoalim Loan bears interest at a fixed rate of 3.45% per annum, payable semi-annually. The Hapoalim Loan Agreement includes various affirmative and negative covenants, including a requirement that the Company maintain (i) a financial debt to adjusted EBITDA ratio not to exceed 6, (ii) a minimum equity capital amount (as shown on its consolidated financial statements) of not less than $750 million, and (iii) an equity capital to total assets ratio of not less than 25%. The Hapoalim Loan Agreement includes other customary affirmative and negative covenants, including payment and covenant events of default. HSBC loan On July 15, 2021, the Company entered into a definitive loan agreement (the "HSBC Loan Agreement") with HSBC Bank PLC. (the “HSBC Bank”). The HSBC Loan Agreement provides for a loan by HSBC Bank to the Company in an aggregate principal amount of $50 million (the “ HSBC Loan”). The outstanding principal amount of the HSBC Loan will be repaid in 14 semi-annual payments of $3.6 million each, commencing on January 19, 2022. The duration of the HSBC Loan is 7 years. The HSBC Loan bears interest at a fixed rate of 3.45% per annum, payable semi-annually. The HSBC Loan Agreement includes various affirmative and negative covenants, including a requirement that the Company maintain (i) a financial debt to adjusted EBITDA ratio not to exceed 6, (ii) a minimum equity capital amount (as shown on its consolidated financial statements) of not less than $750 million, and (iii) an equity capital to total assets ratio of not less than 25%. The HSBC Loan Agreement includes other customary affirmative and negative covenants, including payment and covenant events of default. The proceeds from the Hapoalim Loan and the HSBC Loan were used to pay for the purchase of the geothermal assets portfolio from TG Geothermal Portfolio, LLC as described above.

Note 12 - Subsequent Events

6 Months Ended

Jun. 30, 2021

NOTE 12 — SUBSEQUENT EVENTS

Cash Dividend

On August 4, 2021, the Board of Directors of the Company declared, approved and authorized payment of a quarterly dividend of $6.7 million ($0.12 per share) to all holders of the Company’s issued and outstanding shares of common stock on August 18, 2021, payable on September 1, 2021.

Geothermal assets purchase transaction

On July 14, 2021, the Company closed a transaction with TG Geothermal Portfolio, LLC (a subsidiary of Terra-Gen, LLC) to acquire two contracted geothermal assets in Nevada with a total net generating capacity of 67.5 MW, a greenfield development asset adjacent to one of the plants, and an underutilized transmission line. The Company paid approximately $171 million (excluding working capital and assumed cash, which are subject to final audit) for 100% of the equity interests and assumed debt and associated lease obligations with a book value of approximately $206 million as of June 30, 2021. The two contracted geothermal assets include the Dixie Valley and Beowawe geothermal power plants which sell power under existing power purchase agreements with Southern California Edison under a long term PPA expiring in 2038 and with NV Power, Inc. under a PPA expiring in December 2025, respectively.

The Company will account for the transaction under ASC 805, Business Combinations and is currently evaluating the accounting related to the transaction. The Company expects to consolidate acquired assets in its consolidated financial statements starting at the acquisition date.

Hapoalim loan

On July 12, 2021, the Company entered into a definitive loan agreement (the "Hapoalim Loan Agreement") with Bank Hapoalim B.M. (the “Bank Hapoalim”). The Hapoalim Loan Agreement provides for a loan by Bank Hapoalim to the Company in an aggregate principal amount of $125 million (the “Hapoalim Loan”). The outstanding principal amount of the Hapoalim Loan will be repaid in 14 semi-annual payments of $8.9 million each, commencing on December 12, 2021. The duration of the Hapoalim Loan is 7 years. The Hapoalim Loan bears interest at a fixed rate of 3.45% per annum, payable semi-annually.

The Hapoalim Loan Agreement includes various affirmative and negative covenants, including a requirement that the Company maintain (i) a financial debt to adjusted EBITDA ratio not to exceed 6, (ii) a minimum equity capital amount (as shown on its consolidated financial statements) of not less than $750 million, and (iii) an equity capital to total assets ratio of not less than 25%.

The Hapoalim Loan Agreement includes other customary affirmative and negative covenants, including payment and covenant events of default.

HSBC loan

On July 15, 2021, the Company entered into a definitive loan agreement (the "HSBC Loan Agreement") with HSBC Bank PLC. (the “HSBC Bank”). The HSBC Loan Agreement provides for a loan by HSBC Bank to the Company in an aggregate principal amount of $50 million (the “ HSBC Loan”). The outstanding principal amount of the HSBC Loan will be repaid in 14 semi-annual payments of $3.6 million each, commencing on January 19, 2022. The duration of the HSBC Loan is 7 years. The HSBC Loan bears interest at a fixed rate of 3.45% per annum, payable semi-annually.

The HSBC Loan Agreement includes various affirmative and negative covenants, including a requirement that the Company maintain (i) a financial debt to adjusted EBITDA ratio not to exceed 6, (ii) a minimum equity capital amount (as shown on its consolidated financial statements) of not less than $750 million, and (iii) an equity capital to total assets ratio of not less than 25%.

The HSBC Loan Agreement includes other customary affirmative and negative covenants, including payment and covenant events of default.

The proceeds from the Hapoalim Loan and the HSBC Loan were used to pay for the purchase of the geothermal assets portfolio from TG Geothermal Portfolio, LLC as described above.