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Investment Funds (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | ---
Jul. 01, 2022 | Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021 | Dec. 31, 2021
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Unfunded commitments |  | $ 440,000 |  | $ 440,000 |  |
Investment funds |  | 1,702,270 |  | 1,702,270 |  | $ 1,480,612
Income (Loss) from Investment Funds |  |  |  | 85,874 | $ 100,246 |
Written premiums ceded |  | 466,766 | $ 449,055 | $ 913,349 | 883,729 |
Lifson Re |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Percentage of reinsurance placements of share placed amounts |  |  |  | 22.50% |  |
Written premiums ceded |  |  |  | $ 226,000 | 139,000 |
Lifson Re | Subsequent event |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Percentage of reinsurance placements of share placed amounts | 30.00% |  |  |  |  |
Financial services |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Investment funds |  | 275,075 |  | 275,075 |  | 273,690
Income (Loss) from Investment Funds |  |  |  | 28,243 | 10,506 |
Transportation |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Investment funds |  | 469,474 |  | 469,474 |  | 431,818
Income (Loss) from Investment Funds |  |  |  | 24,135 | 48,990 |
Real Estate |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Investment funds |  | 338,555 |  | 338,555 |  | 336,688
Income (Loss) from Investment Funds |  |  |  | 25,355 | 17,177 |
Energy |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Investment funds |  | 132,728 |  | 132,728 |  | 150,224
Income (Loss) from Investment Funds |  |  |  | 3,708 | 9,492 |
Infrastructure |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Investment funds |  | 110,491 |  | 110,491 |  | 12,314
Income (Loss) from Investment Funds |  |  |  | (133) | 699 |
Other funds |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Investment funds |  | 375,947 |  | 375,947 |  | 275,878
Income (Loss) from Investment Funds |  |  |  | 4,566 | $ 13,382 |
Deferred compensation trust assets |  | $ 31,000 |  | $ 31,000 |  | $ 34,000

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