General - Effects of Reinsurance (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Premiums Earned
Ceded	$ (106,700)	$ (31,100)
Net	1,283,069	1,166,679
Reinsurance Contract [Axis]: Property Quota Share Reinsurance Contract ("Quota Share")
Premiums Written
Assumed	11,000
Property & Casualty
Premiums Written
Direct	1,438,467	1,294,475
Ceded	(156,795)	(31,299)
Assumed	25,733	15,159
Net	1,307,405	1,278,335
Premiums Earned
Direct	1,375,923	1,186,585
Ceded	(106,694)	(31,079)
Assumed	6,529	3,863
Net	$ 1,275,758	$ 1,159,369

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