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Investment Funds (Schedule of Investment Funds) (Details) - USD ($) $ in Thousands |  |  | 12 Months Ended
--- | --- | --- | ---
Jul. 01, 2022 | Jan. 01, 2021 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Maximum loss exposure |  |  | $ 402,000 |  |
Investment funds |  |  | 1,608,548 | $ 1,480,612 |
Income (Loss) From Investment Funds For the Year Ended |  |  | 145,099 | 220,014 | $ 54,253
Ceded to Other Companies |  |  | 1,904,982 | 1,837,267 | 1,585,210
Deferred compensation trust assets |  |  | 30,000 | 34,000 |
Lifson Re |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Ceded to Other Companies |  |  | 399,000 | 245,000 |
Percentage of reinsurance placements of share placed amounts | 30.00% | 22.50% |  |  |
Financial services |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Investment funds |  |  | 465,683 | 431,818 |
Income (Loss) From Investment Funds For the Year Ended |  |  | 34,030 | 98,893 | 34,763
Transportation |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Investment funds |  |  | 336,753 | 336,688 |
Income (Loss) From Investment Funds For the Year Ended |  |  | 53,180 | 42,424 | (616)
Real estate |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Investment funds |  |  | 204,644 | 273,690 |
Income (Loss) From Investment Funds For the Year Ended |  |  | 48,723 | 29,484 | 7,543
Energy |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Investment funds |  |  | 116,432 | 150,224 |
Income (Loss) From Investment Funds For the Year Ended |  |  | 1,425 | 22,118 | (11,039)
Infrastructure |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Investment funds |  |  | 115,428 | 12,314 |
Income (Loss) From Investment Funds For the Year Ended |  |  | 4,603 | 1,372 | 1,672
Other funds |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Investment funds |  |  | 369,608 | 275,878 |
Income (Loss) From Investment Funds For the Year Ended |  |  | $ 3,138 | $ 25,723 | $ 21,930

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