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Short-Term and Long-Term Borrowings - Schedule of Lines of Credit (Details) - USD ($) | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Line of Credit Facility [Line Items] |  |
Line Limit | $ 390,000,000 |
Amount Outstanding | 69,615,000 | $ 81,422,000
Letters of Credit | 8,772,000 |
Amount Available | 311,613,000 | 249,446,000
OTC Credit Agreement |  |
Line of Credit Facility [Line Items] |  |
Line Limit | 170,000,000 |
Amount Outstanding | 0 |
Letters of Credit | 0 |
Amount Available | 170,000,000 | 170,000,000
OTP Credit Agreement |  |
Line of Credit Facility [Line Items] |  |
Line Limit | 220,000,000 |
Amount Outstanding | 69,615,000 |
Letters of Credit | 8,772,000 |
Amount Available | $ 141,613,000 | $ 79,446,000

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