CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
INTEREST AND DIVIDEND INCOME:
Loans, including related fees	$ 128,000	$ 137,241	$ 124,788
Securities:
Taxable	13,998	13,625	15,191
Tax-exempt	8,762	7,952	7,674
Other	1,438	1,667	1,468
TOTAL INTEREST AND DIVIDEND INCOME	152,198	160,485	149,121
INTEREST EXPENSE:
Interest Expense, Deposits	8,158	12,801	15,711
Short-term borrowings	387	568	1,105
Other borrowings	252	770	653
TOTAL INTEREST EXPENSE	8,797	14,139	17,469
NET INTEREST INCOME	143,401	146,346	131,652
Provision for credit loss expense	2,466	10,528	4,700
NET INTEREST INCOME AFTER PROVISION FOR CREDIT LOSSES	140,935	135,818	126,952
Trust And Financial Services Revenue	5,255	5,423	5,036
Service Charges And Fees On Deposit Accounts	10,089	10,256	11,795
Service Charges And Fees, Other	18,212	15,644	14,012
NON-INTEREST INCOME:
Securities gain (loss), net	114	233	44
Insurance commissions	162	158	133
Gain on sale of mortgage loans	5,003	6,626	2,573
Other	3,249	4,136	4,859
TOTAL NON-INTEREST INCOME	42,084	42,476	38,452
Labor and Related Expense	64,474	61,931	54,827
NON-INTEREST EXPENSES:
Occupancy expense	8,774	8,202	7,600
Equipment expense	10,174	10,568	8,244
Federal Deposit Insurance	1,294	316	693
Other	32,690	31,741	33,041
TOTAL NON-INTEREST EXPENSE	117,406	112,758	104,405
INCOME BEFORE INCOME TAXES	65,613	65,536	60,999
Provision for income taxes	12,626	11,692	12,127
NET INCOME	52,987	53,844	48,872
OTHER COMPREHENSIVE INCOME
Change in unrealized gains/losses on securities, net of reclassifications and taxes	(18,488)	19,269	20,998
Change in funded status of post-retirement benefits, net of taxes	6,298	(2,004)	(5,045)
COMPREHENSIVE INCOME	$ 40,797	$ 71,109	$ 64,825
EARNINGS PER SHARE:
BASIC AND DILUTED (in dollars per share)	$ 4.02	$ 3.93	$ 3.80
Weighted average number of shares outstanding (in shares)	13,190	13,716	12,865