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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 | Mar. 31, 2025 | Dec. 31, 2024
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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 | $ 411,111 | $ 440,896
Private equity |  |
Other Investment Portfolio By Strategy And Remaining Commitment Amount and Maximum Exposure to Loss Associated With Each Strategy [Line Items] |  |
Carrying Value | 322,644 | 346,020
Remaining Commitment | 180,116 | 182,355
Maximum Exposure to Loss | 502,760 | 528,375
Private credit |  |
Other Investment Portfolio By Strategy And Remaining Commitment Amount and Maximum Exposure to Loss Associated With Each Strategy [Line Items] |  |
Carrying Value | 46,294 | 52,100
Remaining Commitment | 111,299 | 99,185
Maximum Exposure to Loss | 157,593 | 151,285
Real assets |  |
Other Investment Portfolio By Strategy And Remaining Commitment Amount and Maximum Exposure to Loss Associated With Each Strategy [Line Items] |  |
Carrying Value | 42,173 | 42,776
Remaining Commitment | 38,480 | 38,950
Maximum Exposure to Loss | 80,653 | 81,726
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 | 411,111 | 440,896
Remaining Commitment | 329,895 | 320,490
Maximum Exposure to Loss | $ 741,006 | $ 761,386

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