Employee Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Employees' Stock Ownership Plan
Number of allocated shares acquired prior to December 31, 1992	113,866	115,602
Associated fair values of allocated shares acquired prior to December 31, 1992	$ 3.1	$ 2.8
Shares
Allocated shares	36,719	36,639
Fair Value
Allocated shares, Fair Value	$ 1.0	$ 0.9
Profit Sharing Plan
Vesting period	5 years
Expenses related to employee benefit plans
Employee benefits	$ 5.8	5.4	$ 5.1
Deferred compensation plans for deferral of performance bonuses
Deferred compensation expense	0.1	0.3	$ 0.3
Deferred compensation liability	0.4	$ 6.4
Banc Ed
Deferred compensation plans for deferral of performance bonuses
Deferred compensation liability	$ 0.4