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Investments - Schedule of Alternative Investment Portfolio by Strategy and the Remaining Commitment Amount and Maximum Exposure to Loss Associated With Each Strategy (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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Other Investment Portfolio By Strategy And Remaining Commitment Amount and Maximum Exposure to Loss Associated With Each Strategy [Line Items] |  |
Carrying Value | $ 101,065 | $ 91,164
Total alternative investments |  |
Other Investment Portfolio By Strategy And Remaining Commitment Amount and Maximum Exposure to Loss Associated With Each Strategy [Line Items] |  |
Carrying Value | 440,896 | 395,779
Remaining Commitment | 320,490 | 254,326
Maximum Exposure to Loss | 761,386 | 650,105
Private equity |  |
Other Investment Portfolio By Strategy And Remaining Commitment Amount and Maximum Exposure to Loss Associated With Each Strategy [Line Items] |  |
Carrying Value | 346,020 | 301,759
Remaining Commitment | 182,355 | 131,885
Maximum Exposure to Loss | 528,375 | 433,644
Private credit |  |
Other Investment Portfolio By Strategy And Remaining Commitment Amount and Maximum Exposure to Loss Associated With Each Strategy [Line Items] |  |
Carrying Value | 52,100 | 54,500
Remaining Commitment | 99,185 | 89,401
Maximum Exposure to Loss | 151,285 | 143,901
Real assets |  |
Other Investment Portfolio By Strategy And Remaining Commitment Amount and Maximum Exposure to Loss Associated With Each Strategy [Line Items] |  |
Carrying Value | 42,776 | 39,520
Remaining Commitment | 38,950 | 33,040
Maximum Exposure to Loss | $ 81,726 | $ 72,560

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