CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
INTEREST AND DIVIDEND INCOME:
Loans, including related fees	$ 86,128	$ 84,022	$ 87,530
Securities:
Taxable	14,506	15,815	17,015
Tax-exempt	7,269	7,194	7,084
Other	1,477	1,645	1,729
TOTAL INTEREST AND DIVIDEND INCOME	109,380	108,676	113,358
INTEREST EXPENSE:
Deposits	4,159	3,934	4,624
Short-term borrowings	134	70	99
Other borrowings	114	165	803
TOTAL INTEREST EXPENSE	4,407	4,169	5,526
NET INTEREST INCOME	104,973	104,507	107,832
Provision for loan losses	3,300	4,700	5,072
NET INTEREST INCOME AFTER PROVISION FOR LOAN LOSSES	101,673	99,807	102,760
NON-INTEREST INCOME:
Trust and financial services	5,208	5,586	5,860
Service charges and fees on deposit accounts	10,530	10,145	10,772
Other service charges and fees	12,307	11,798	11,697
Securities gain (loss), net	34	17	(3)
Insurance commissions	2,346	6,945	7,646
Gain on Sale of certain assets and liabilities of Insurance Brokerage Operation	12,822	0	0
Gain on sale of mortgage loans	1,842	1,998	1,849
Other	1,842	2,690	2,964
TOTAL NON-INTEREST INCOME	46,931	39,179	40,785
Labor and Related Expense	52,730	60,109	55,936
NON-INTEREST EXPENSES:
Occupancy expense	6,865	6,978	7,218
Equipment expense	7,300	6,991	7,269
Federal Deposit Insurance	1,300	1,769	1,931
Other	22,113	22,551	23,230
TOTAL NON-INTEREST EXPENSE	90,308	98,398	95,584
INCOME BEFORE INCOME TAXES	58,296	40,588	47,961
Provision for income taxes	19,883	10,392	14,189
NET INCOME	38,413	30,196	33,772
OTHER COMPREHENSIVE INCOME
Change in unrealized gains/losses on securities, net of reclassifications and taxes	(10,130)	(1,225)	13,913
Change in funded status of post-retirement benefits, net of taxes	5,367	$ 6,353	$ (14,473)
COMPREHENSIVE INCOME	$ 33,650
EARNINGS PER SHARE:
BASIC AND DILUTED (in dollars per share)	$ 3.12	$ 2.35	$ 2.55
Weighted average number of shares outstanding (in shares)	12,317	12,836	13,226