Insurance Company Subsidiary Operations - Effects of Reinsurance on Premiums Written and Earned (Details) $ in Millions	6 Months Ended
Jun. 30, 2023 USD ($)
Written
Net premiums	$ 34.9
Earned
Net premiums	21.7
WNFIC
Written
Direct premiums	412.1
Ceded premiums	(412.1)
Earned
Direct premiums	377.9
Ceded premiums	(377.9)
Quota Share Captive and Excess of Loss Layer Captive
Written
Assumed Premiums	75.9
Net premiums	34.9
Earned
Assumed Premium	38.7
Net premiums	21.7
Quota Share Captive
Written
Ceded premiums	(41.0)
Net premiums	33.3
Earned
Ceded premiums	(17.0)
Net premiums	$ 20.1

Amount of earned premiums assumed from other entities.

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