Schedule I-Summary Of Investments-Other than Investments in Related Parties (Details) $ in Thousands	Dec. 31, 2024 USD ($)
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	$ 3,979,169
Fair Value	4,084,631
Amount at which shown in the balance sheet	4,084,631
Fixed Maturities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	3,391,159
Fair Value	3,175,796
Amount at which shown in the balance sheet	3,175,796
Available-for-Sale
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	3,391,159
Fair Value	3,175,796
Amount at which shown in the balance sheet	3,175,796
Equity Securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	417,897
Fair Value	736,191
Amount at which shown in the balance sheet	736,191
Ind Misc & All Other
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	125,827
Fair Value	219,832
Amount at which shown in the balance sheet	219,832
ETFs (Ind/misc)
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	292,070
Fair Value	516,359
Amount at which shown in the balance sheet	516,359
Cash and Short-term Investments
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	114,705
Fair Value	114,705
Amount at which shown in the balance sheet	114,705
Other Invested Assets
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	55,408
Fair Value	57,939
Amount at which shown in the balance sheet	57,939
U.S. government | Available-for-Sale
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	525,608
Fair Value	515,635
Amount at which shown in the balance sheet	515,635
U.S. Agency | Available-for-Sale
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	55,921
Fair Value	54,338
Amount at which shown in the balance sheet	54,338
Non-U.S. government & agency | Available-for-Sale
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	8,959
Fair Value	7,871
Amount at which shown in the balance sheet	7,871
Agency MBS | Available-for-Sale
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	438,545
Fair Value	396,223
Amount at which shown in the balance sheet	396,223
ABS/CMBS/MBS | Available-for-Sale
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	430,973
Fair Value	410,248
Amount at which shown in the balance sheet	410,248
Corporate | Available-for-Sale
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	1,397,676
Fair Value	1,346,521
Amount at which shown in the balance sheet	1,346,521
Municipal | Available-for-Sale
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	533,477
Fair Value	444,960
Amount at which shown in the balance sheet	$ 444,960