General - Effects of Reinsurance (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Premiums Earned
Ceded	$ (54,400)		$ (31,400)	$ (161,100)	$ (62,500)
Net	1,366,738		1,236,024	2,649,808	2,402,703
Reinsurance Contract [Axis]: 100% Reinsurance Limit Used
Premiums Written
Ceded	0	$ (52,000)		(52,000)
Premiums Earned
Ceded	0	(52,000)		(52,000)
Reinsurance Contract [Axis]: Pro-Forma, $0 Reinsurance Limit
Premiums Written
Ceded	(26,000)	(26,000)		(52,000)
Premiums Earned
Ceded	(26,000)	$ (26,000)		(52,000)
Reinsurance Contract [Axis]: Property Quota Share Reinsurance Contract ("Quota Share")
Premiums Written
Assumed				11,000
Property & Casualty
Premiums Written
Direct	1,477,169		1,380,511	2,915,636	2,674,986
Ceded	(3,939)		(31,884)	(160,735)	(63,183)
Assumed	(238)		85	25,494	15,244
Net	1,472,992		1,348,712	2,780,395	2,627,047
Premiums Earned
Direct	1,407,608		1,256,208	2,783,531	2,442,793
Ceded	(54,405)		(31,371)	(161,099)	(62,450)
Assumed	6,139		3,859	12,668	7,722
Net	$ 1,359,342		$ 1,228,696	$ 2,635,100	$ 2,388,065

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