Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Segment Reporting Information [Line Items]
Goodwill and other intangibles	$ 51,608		$ 51,608		$ 42,645
Total assets	2,989,179		2,989,179		2,449,158
Net interest income	24,165	$ 20,757	70,388	$ 61,213
Provision for loan losses	2,600	550	6,100	1,850
Service fees, security gains and other noninterest income	9,467	7,441	26,473	20,955
Noninterest expense	16,944	15,717	51,880	46,970
Amortization and depreciation expense	776	706	2,317	2,134
INCOME BEFORE INCOME TAXES	13,312	11,225	36,564	31,214
Income taxes	2,443	2,071	6,045	5,129
NET INCOME	10,869	9,154	30,519	26,085
Eliminations And Others
Segment Reporting Information [Line Items]
Goodwill and other intangibles	(3,558)		(3,558)		(822)
Total assets	4,175		4,175		4,482
Net interest income	(63)	(20)	(247)	(65)
Provision for loan losses	0	0	0	0
Service fees, security gains and other noninterest income	(64)	(71)	(346)	(199)
Noninterest expense	63	321	634	734
Amortization and depreciation expense	68	13	184	37
INCOME BEFORE INCOME TAXES	(258)	(425)	(1,411)	(1,035)
Income taxes	(120)	(110)	(476)	(360)
NET INCOME	(138)	(315)	(935)	(675)
Trust Segment | Operating Segments
Segment Reporting Information [Line Items]
Goodwill and other intangibles	6,116		6,116		6,326
Total assets	14,500		14,500		13,892
Net interest income	31	43	95	121
Provision for loan losses	0	0	0	0
Service fees, security gains and other noninterest income	2,357	2,277	6,922	6,825
Noninterest expense	1,520	1,459	4,549	4,580
Amortization and depreciation expense	75	91	228	275
INCOME BEFORE INCOME TAXES	793	770	2,240	2,091
Income taxes	166	162	470	440
NET INCOME	627	608	1,770	1,651
Bank Segment | Operating Segments
Segment Reporting Information [Line Items]
Goodwill and other intangibles	49,050		49,050		37,141
Total assets	2,970,504		2,970,504		$ 2,430,784
Net interest income	24,197	20,734	70,540	61,157
Provision for loan losses	2,600	550	6,100	1,850
Service fees, security gains and other noninterest income	7,174	5,235	19,897	14,329
Noninterest expense	15,361	13,937	46,697	41,656
Amortization and depreciation expense	633	602	1,905	1,822
INCOME BEFORE INCOME TAXES	12,777	10,880	35,735	30,158
Income taxes	2,397	2,019	6,051	5,049
NET INCOME	$ 10,380	$ 8,861	$ 29,684	$ 25,109