Segment Reporting (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) item segment	Sep. 30, 2020 USD ($)
Segment Reporting
Number of operating segments | segment			4
Number of banking offices | item			14
Key metrics related to segments
Net interest income	$ 21,132	$ 21,765	$ 64,310	$ 60,693
Provision for loan losses	(2,000)	3,500	(2,000)	9,500
Noninterest income	36,040	45,256	113,669	110,675
Noninterest expense	42,041	40,214	127,633	116,674
Net income before taxes	17,131	23,307	52,346	45,194
Corporate Administration
Key metrics related to segments
Net interest income	(535)	(842)	(1,361)	(2,575)
Noninterest income	22	(1)	(6)	8
Noninterest expense	9,635	9,112	27,152	26,833
Net income before taxes	(10,148)	(9,955)	(28,519)	(29,400)
Banking | Operating Segments
Key metrics related to segments
Net interest income	21,168	21,994	64,236	61,857
Provision for loan losses	(2,000)	3,500	(2,000)	9,500
Noninterest income	1,576	3,398	4,564	8,129
Noninterest expense	11,403	10,876	33,401	34,887
Net income before taxes	13,341	11,016	37,399	25,599
Retirement and Benefit Services | Operating Segments
Key metrics related to segments
Noninterest income	18,031	15,104	53,157	45,034
Noninterest expense	10,320	8,347	30,420	25,472
Net income before taxes	7,711	6,757	22,737	19,562
Wealth Management | Operating Segments
Key metrics related to segments
Noninterest income	5,295	4,486	15,419	12,644
Noninterest expense	2,219	2,110	6,682	6,254
Net income before taxes	3,076	2,376	8,737	6,390
Mortgage | Operating Segments
Key metrics related to segments
Net interest income	499	613	1,435	1,411
Noninterest income	11,116	22,269	40,535	44,860
Noninterest expense	8,464	9,769	29,978	23,228
Net income before taxes	$ 3,151	$ 13,113	$ 11,992	$ 23,043