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Short-term Debt (Details 1) - USD ($) $ in Thousands | Mar. 31, 2022 | Mar. 18, 2022 | Dec. 31, 2021 | Mar. 31, 2021
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Short-term Debt [Line Items] |  |  |  |
Short-term borrowings | $ 99,958 |  | $ 0 | $ 50,000
Term Loan Agreement | Centennial Energy Holdings, Inc. |  |  |  |
Short-term Debt [Line Items] |  |  |  |
Short-term borrowings |  | $ 100,000 |  |
Ratio of total debt to total capitalization as specified in debt covenants | 65.00% |  |  |

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