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Investments - Maturity Table (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,742,863	$ 2,042,473
Estimated Fair Value	1,650,656	$ 1,933,226
2026
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	549,417
Estimated Fair Value	531,168
2027
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	99,219
Estimated Fair Value	97,955
2038
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	64
Estimated Fair Value	65
2039
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	531
Estimated Fair Value	522
2042
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,894
Estimated Fair Value	1,647
2043
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,593
Estimated Fair Value	3,223
2044
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,001
Estimated Fair Value	3,647
2045
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,319
Estimated Fair Value	3,835
2046
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	6,834
Estimated Fair Value	5,990
2047
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	6,282
Estimated Fair Value	5,516
2048
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,678
Estimated Fair Value	1,492
2049
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	13,929
Estimated Fair Value	12,279
2050
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	98,147
Estimated Fair Value	77,538
2051
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	139,167
Estimated Fair Value	108,529
2052
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	53,864
Estimated Fair Value	47,250
2053
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	276,396
Estimated Fair Value	272,424
2054
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	131,424
Estimated Fair Value	126,298
2055
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	134,514
Estimated Fair Value	132,583
2056
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	181,834
Estimated Fair Value	182,473
2058
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	35,756
Estimated Fair Value	$ 36,222

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