Reinsurance (Cumulative Paid Claims) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cumulative Paid Claims [Line Items]
Cumulative Paid Claims	$ 152.7
Incident Year - Four Years Prior [Member]
Cumulative Paid Claims [Line Items]
Cumulative Paid Claims	22.6	$ 22.6	$ 22.6	$ 22.5	$ 21.3
Incident Year - Three Years Prior [Member]
Cumulative Paid Claims [Line Items]
Cumulative Paid Claims	25.8	25.8	25.7	$ 24.2
Incident Year - Two Years Prior [Member]
Cumulative Paid Claims [Line Items]
Cumulative Paid Claims	30.2	30.2	$ 28.3
Incident Year - Prior Year [Member]
Cumulative Paid Claims [Line Items]
Cumulative Paid Claims	37.6	$ 35.4
Incident Year - Current Year [Member]
Cumulative Paid Claims [Line Items]
Cumulative Paid Claims	$ 36.5