Business Segments (Statement of Operations and Total Assets by Reportable Segment) (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]
Net interest income (expense)	[1]	$ 31,654	$ 32,978	$ 95,201	$ 101,420
Provision for credit losses		1,325	400	10,561	1,575
Net interest income after provision for credit losses		30,329	32,578	84,640	99,845
Noninterest income	[1]	25,468	18,342	71,715	50,462
Depreciation and amortization expense		989	1,042	3,006	3,192
Other noninterest expenses related to segments		31,355	25,828	88,269	78,793
Total noninterest expense		32,344	26,870	91,275	81,985
Income before income taxes		23,453	24,050	65,080	68,322
Income tax expense		5,131	5,236	13,817	14,740
Net income		18,322	18,814	51,263	53,582
Total assets		5,849,792	5,198,878	5,849,792	5,198,878	$ 5,292,659
Expenditures for long-lived assets		406	797	1,331	2,768
Commercial Banking [Member]
Segment Reporting Information [Line Items]
Net interest income (expense)		33,103	28,515	94,692	83,684
Provision for credit losses		1,325	400	10,561	1,575
Net interest income after provision for credit losses		31,778	28,115	84,131	82,109
Noninterest income		15,940	8,607	43,515	20,753
Depreciation and amortization expense		601	642	1,832	1,985
Other noninterest expenses related to segments		20,273	16,255	56,571	48,676
Total noninterest expense		20,874	16,897	58,403	50,661
Income before income taxes		26,844	19,825	69,243	52,201
Income tax expense		5,828	4,347	14,769	11,371
Net income		21,016	15,478	54,474	40,830
Total assets		4,588,419	3,994,458	4,588,419	3,994,458
Expenditures for long-lived assets		360	662	1,147	2,259
Wealth Management Services [Member]
Segment Reporting Information [Line Items]
Net interest income (expense)		(24)	(114)	(117)	(361)
Provision for credit losses		0	0	0	0
Net interest income after provision for credit losses		(24)	(114)	(117)	(361)
Noninterest income		8,954	9,153	26,248	27,961
Depreciation and amortization expense		350	360	1,058	1,089
Other noninterest expenses related to segments		7,178	6,217	20,408	19,631
Total noninterest expense		7,528	6,577	21,466	20,720
Income before income taxes		1,402	2,462	4,665	6,880
Income tax expense		403	646	1,216	1,845
Net income		999	1,816	3,449	5,035
Total assets		74,942	78,812	74,942	78,812
Expenditures for long-lived assets		20	87	86	379
Corporate [Member]
Segment Reporting Information [Line Items]
Net interest income (expense)		(1,425)	4,577	626	18,097
Provision for credit losses		0	0	0	0
Net interest income after provision for credit losses		(1,425)	4,577	626	18,097
Noninterest income		574	582	1,952	1,748
Depreciation and amortization expense		38	40	116	118
Other noninterest expenses related to segments		3,904	3,356	11,290	10,486
Total noninterest expense		3,942	3,396	11,406	10,604
Income before income taxes		(4,793)	1,763	(8,828)	9,241
Income tax expense		(1,100)	243	(2,168)	1,524
Net income		(3,693)	1,520	(6,660)	7,717
Total assets		1,186,431	1,125,608	1,186,431	1,125,608
Expenditures for long-lived assets		$ 26	$ 48	$ 98	$ 130

[1] As reported in the Consolidated Statements of Income.