Insurance Company Subsidiary Operations - Effects of Reinsurance on Premiums Written and Earned (Details) $ in Millions	9 Months Ended
Sep. 30, 2025 USD ($)
Written
Net premiums	$ 75
Earned
Net premiums	57
WNFIC
Written
Direct premiums	838
Ceded premiums	(838)
Earned
Direct premiums	773
Ceded premiums	(773)
Captive
Written
Direct premiums	159
Assumed Premiums	133
Ceded premiums	(217)
Net premiums	75
Earned
Direct premiums	326
Assumed Premium	106
Ceded premiums	(375)
Net premiums	$ 57

Amount of earned premiums assumed from other entities.

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