Investment Funds (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
Unfunded commitments	$ 615,000
Investment funds	1,545,648		$ 1,480,612
Income (Loss) from Investment Funds	52,014	$ 38,935
Written premiums ceded	$ 446,582	434,674
Lifson Re
Schedule of Equity Method Investments [Line Items]
Percentage of reinsurance placements of share placed amounts	22.50%
Written premiums ceded	$ 89,000	53,000
Financial services
Schedule of Equity Method Investments [Line Items]
Investment funds	283,897		273,690
Income (Loss) from Investment Funds	16,364	4,434
Transportation
Schedule of Equity Method Investments [Line Items]
Investment funds	454,701		431,818
Income (Loss) from Investment Funds	25,932	17,142
Real Estate
Schedule of Equity Method Investments [Line Items]
Investment funds	341,022		336,688
Income (Loss) from Investment Funds	11,179	6,228
Energy
Schedule of Equity Method Investments [Line Items]
Investment funds	136,401		150,224
Income (Loss) from Investment Funds	(892)	3,320
Other funds
Schedule of Equity Method Investments [Line Items]
Investment funds	329,627		288,192
Income (Loss) from Investment Funds	(569)	$ 7,811
Deferred compensation trust assets	$ 32,000		$ 34,000

Amount of written premiums ceded to other entities.

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