Insurance Company Subsidiary Operations - Effects of Reinsurance on Premiums Written and Earned (Details) $ in Millions	9 Months Ended
Sep. 30, 2023 USD ($)
Written
Net premiums	$ 39.9
Earned
Net premiums	33.7
WNFIC
Written
Direct premiums	681.8
Ceded premiums	(681.8)
Earned
Direct premiums	588.2
Ceded premiums	(588.2)
Quota Share Captive and Excess of Loss Layer Captive
Written
Assumed Premiums	86.2
Net premiums	39.9
Earned
Assumed Premium	63.3
Net premiums	33.7
Quota Share Captive
Written
Ceded premiums	(46.3)
Net premiums	37.4
Earned
Ceded premiums	(29.6)
Net premiums	$ 31.2

Amount of earned premiums assumed from other entities.

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Amount of earned premiums ceded to other entities.

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