Other Real Estate Owned (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Repossessed Assets [Abstract]
Real Estate Acquired Through Foreclosure, Valuation Adjustments	$ 1.1	$ 2.8	$ 0.0
Real Estate Acquired Through Foreclosure [Roll Forward]
Balance at beginning of year	12.7	2.0	2.5
Acquired through acquisitions	0.0	15.8	0.0
Additions	8.3	0.4	0.9
Dispositions	(3.4)	(2.7)	(1.4)
Balance at end of year	16.5	$ 12.7	$ 2.0
Mortgage Loans in Process of Foreclosure, Amount	0.5
Carrying value of foreclosed OREO	$ 0.0