Income Tax - Reconciliation of Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Currently payable
Federal	$ 16,914	$ 11,143	$ 9,166
State	2,377	140	0
Deferred
Federal	(7,970)	1,787	1,277
State	(1,451)	233	0
Total income tax expense	9,870	13,303	10,443
Reconciliation of federal statutory to actual tax expense
Federal statutory income tax at 21%	16,457	16,767	13,348
Tax exempt interest	(4,090)	(2,977)	(1,982)
Tax exempt income	(531)	(587)	(448)
Stock compensation	(160)	(324)	(384)
Other tax exempt income	(334)	(313)	(260)
State tax	733	295	0
Tax credit investments	(2,284)	0	0
Nondeductible and other	79	442	169
Total income tax expense	$ 9,870	$ 13,303	$ 10,443