Significant Accounting Policies (Details) $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($) segment	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Significant Accounting Policies
Number of operating segments | segment	4
Percentage of commercial and industrial loans not secured by real estate	23.90%	24.80%
Period when accrual of interest on loans is discontinued when loans are past due	90 days
Unrecognized tax position pertaining to interest and penalties | $	$ 0.0	$ 0.0	$ 0.0
Maximum
Significant Accounting Policies
Period when consumer loans are charged off when loans are past due	120 days