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Investment Funds (Details) - USD ($) $ in Thousands |  | 3 Months Ended |
--- | --- | --- | ---
Jul. 01, 2022 | Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022
Schedule of Equity Method Investments [Line Items] |  |  |  |
Unfunded commitments |  | $ 408,000 |  |
Investment funds |  | 1,601,567 |  | $ 1,608,548
Income (Loss) from Investment Funds |  | 2,180 | $ 52,012 |
Written premiums ceded |  | 474,493 | 446,582 |
Fair Value |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Trading account receivables from brokers and clearing organizations |  | $ 583,970 |  | 233,863
Lifson Re |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Percentage of reinsurance placements of share placed amounts | 30.00% | 22.50% |  |
Written premiums ceded |  | $ 107,000 | 89,000 |
Financial services |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Investment funds |  | 216,871 |  | 204,644
Income (Loss) from Investment Funds |  | 956 | 16,364 |
Transportation |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Investment funds |  | 444,645 |  | 465,683
Income (Loss) from Investment Funds |  | (13,047) | 25,932 |
Real Estate |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Investment funds |  | 336,808 |  | 336,753
Income (Loss) from Investment Funds |  | 11,788 | 11,179 |
Energy |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Investment funds |  | 117,461 |  | 116,432
Income (Loss) from Investment Funds |  | 3,439 | (892) |
Infrastructure |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Investment funds |  | 119,042 |  | 115,428
Income (Loss) from Investment Funds |  | 3,355 | 841 |
Other funds |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Investment funds |  | 366,740 |  | 369,608
Income (Loss) from Investment Funds |  | (4,311) | $ (1,412) |
Deferred compensation trust assets |  | $ 34,000 |  | $ 30,000

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