Reinsurance (Cumulative Paid Claims) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cumulative Paid Claims [Line Items]
Cumulative Paid Claims	$ 218.2
Incident Year - Four Years Prior [Member]
Cumulative Paid Claims [Line Items]
Cumulative Paid Claims	30.2	$ 30.2	$ 30.2	$ 30.2	$ 28.3
Incident Year - Three Years Prior [Member]
Cumulative Paid Claims [Line Items]
Cumulative Paid Claims	37.7	37.7	37.6	$ 35.4
Incident Year - Two Years Prior [Member]
Cumulative Paid Claims [Line Items]
Cumulative Paid Claims	39.3	39.2	$ 36.5
Incident Year - Prior Year [Member]
Cumulative Paid Claims [Line Items]
Cumulative Paid Claims	47.7	$ 42.9
Incident Year - Current Year [Member]
Cumulative Paid Claims [Line Items]
Cumulative Paid Claims	$ 63.3