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Investments (Alternative Investment Portfolio by Strategy and the Remaining Commitment Amount Associated With Each Strategy) (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
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Carrying Value | $ 91,164 | $ 71,244
Private Equity [Member] |  |
Carrying Value | 301,759 | 280,980
Remaining Commitment | 131,885 | 134,676
Maximum Exposure to Loss | 433,644 | 415,656
Private Credit Funds [Member] |  |
Carrying Value | 54,500 | 54,866
Remaining Commitment | 89,401 | 89,481
Maximum Exposure to Loss | 143,901 | 144,347
Real Assets [Member] |  |
Carrying Value | 39,520 | 35,470
Remaining Commitment | 33,040 | 21,945
Maximum Exposure to Loss | 72,560 | 57,415
Alternative Investments [Member] |  |
Carrying Value | 395,779 | 371,316
Remaining Commitment | 254,326 | 246,102
Maximum Exposure to Loss | $ 650,105 | $ 617,418

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