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Investments - Maturity Table (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 2,563,984 | $ 2,554,332
Estimated Fair Value | 2,411,622 | $ 2,342,089
2024 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 699,496 |
Estimated Fair Value | 686,762 |
2025 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 298,815 |
Estimated Fair Value | 289,794 |
2026 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 548,686 |
Estimated Fair Value | 506,438 |
2027 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 98,612 |
Estimated Fair Value | 95,746 |
2038 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 68 |
Estimated Fair Value | 69 |
2039 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 646 |
Estimated Fair Value | 639 |
2042 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 2,296 |
Estimated Fair Value | 2,002 |
2043 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 4,156 |
Estimated Fair Value | 3,773 |
2044 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 4,837 |
Estimated Fair Value | 4,483 |
2045 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 5,107 |
Estimated Fair Value | 4,596 |
2046 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 7,725 |
Estimated Fair Value | 6,897 |
2047 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 7,646 |
Estimated Fair Value | 6,880 |
2048 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 2,027 |
Estimated Fair Value | 1,971 |
2049 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 15,792 |
Estimated Fair Value | 14,170 |
2050 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 107,611 |
Estimated Fair Value | 87,112 |
2051 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 154,622 |
Estimated Fair Value | 124,399 |
2052 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 53,653 |
Estimated Fair Value | 46,966 |
2053 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 245,209 |
Estimated Fair Value | 236,537 |
2054 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 71,439 |
Estimated Fair Value | 63,426 |
2055 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 86,199 |
Estimated Fair Value | 81,892 |
2056 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 102,609 |
Estimated Fair Value | 100,728 |
2058 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 46,733 |
Estimated Fair Value | $ 46,342 |

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