CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Interest income:
Interest and fees on loans		$ 145,425	$ 165,519	$ 149,932
Interest on mortgage loans held for sale		1,762	1,237	1,212
Taxable interest on debt securities		20,050	26,367	21,816
Nontaxable interest on debt securities		0	18	61
Dividends on Federal Home Loan Bank stock		2,240	2,855	2,369
Other interest income		459	1,667	1,017
Interest and dividend income		169,936	197,663	176,407
Interest expense:
Deposits		25,812	37,101	24,175
Federal Home Loan Bank advances		15,806	26,168	19,073
Junior subordinated debentures		641	980	869
Other interest expense		233	0	0
Interest expense		42,492	64,249	44,117
Net interest income (expense)	[1]	127,444	133,414	132,290
Provision for credit losses		12,342	1,575	1,550
Net interest income after provision for credit losses		115,102	131,839	130,740
Noninterest income:
Wealth management revenues	[1]	35,454	36,848	38,341
Mortgage banking revenues	[1]	47,377	14,795	10,381
Card interchange fees	[1]	4,287	4,214	3,768
Service charges on deposit accounts	[1]	2,742	3,684	3,628
Loan related derivative income	[1]	3,991	3,993	2,461
Income from bank-owned life insurance	[1]	2,491	2,354	2,196
Net realized losses on securities	[1]	0	(53)	0
Other income	[1]	3,100	1,245	1,339
Noninterest income	[1]	99,442	67,080	62,114
Noninterest expense:
Salaries and employee benefits		82,899	72,761	69,277
Outsourced services		11,894	10,598	8,684
Net occupancy		8,023	7,821	7,891
Equipment		3,831	4,081	4,312
Legal, audit and professional fees		3,747	2,535	2,427
FDIC deposit insurance costs		1,818	618	1,612
Advertising and promotion		1,469	1,534	1,406
Amortization of intangibles		914	943	979
Debt prepayment penalties		1,413	0	0
Change in fair value of contingent consideration		0	0	(187)
Other expenses		9,376	9,849	9,761
Noninterest expense		125,384	110,740	106,162
Income before income taxes		89,160	88,179	86,692
Income tax expense		19,331	19,061	18,260
Net income		69,829	69,118	68,432
Net income available to common shareholders		$ 69,678	$ 68,979	$ 68,288
Weighted average common shares outstanding - basic		17,282	17,331	17,272
Weighted average common shares outstanding - diluted		17,402	17,414	17,391
Per share information:
Basic earnings per common share (in dollars per share)		$ 4.03	$ 3.98	$ 3.95
Diluted earnings per common share (in dollars per share)		$ 4.00	$ 3.96	$ 3.93

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