Consolidated Condensed Statements Of Income - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Interest and dividend income:
Interest and fees on loans	$ 72,003,000	$ 64,402,000
Interest and dividends on:
Obligations of U.S. Government, its agencies and other securities	6,995,000	6,767,000
Interest Income, Securities, State and Municipal	2,217,000	2,174,000
Other interest income	641,000	371,000
Total interest and dividend income	81,856,000	73,714,000
Interest on deposits:
Demand and savings deposits	7,093,000	3,290,000
Time deposits	3,777,000	2,551,000
Interest on borrowings:
Short-term borrowings	739,000	575,000
Long-term debt	2,471,000	2,448,000
Total interest expense	14,080,000	8,864,000
Net interest income	67,776,000	64,850,000
Provision for loan losses	2,498,000	260,000
Net interest income after provision for loan losses	65,278,000	64,590,000
Noninterest Income [Abstract]
Debit card fee income	4,369,000	4,002,000
Bank owned life insurance income	1,006,000	1,009,000
ATM Fees	440,000	524,000
OREO valuation adjustments	(27,000)	(207,000)
Gain on sale of OREO, net	(12,000)	4,321,000
Gain (Loss) on Sale of Investments	0	(2,271,000)
Gain on equity securities, net	121,000	3,489,000
Other components of net periodic benefit income	1,183,000	1,705,000
Other	2,845,000	842,000
Total other income	22,025,000	26,903,000
Other expense:
Salaries and employee benefits	25,805,000	25,320,000
Employee Benefits and Share-based Compensation	8,430,000	7,029,000
Occupancy expense	3,011,000	2,936,000
Furniture and equipment expense	4,150,000	4,149,000
Data processing fees	2,133,000	1,773,000
Professional fees and services	6,006,000	6,190,000
Marketing	1,226,000	1,218,000
Insurance	1,156,000	1,428,000
Communication	1,333,000	1,250,000
Excise and Sales Taxes	1,005,000	1,105,000
Amortization of Intangible Assets	289,000	0
Other expense	2,283,000	1,910,000
Total other expense	56,827,000	54,308,000
Income before income taxes	30,476,000	37,185,000
Income taxes	5,021,000	6,062,000
Net income	25,455,000	31,123,000
Net income available to common shareholders	$ 25,455,000	$ 31,123,000
Net income available to common shareholders
Basic	$ 1.63	$ 2.04
Diluted	$ 1.62	$ 2.02
Weighted average common shares outstanding
Basic	15,651,541	15,288,332
Diluted	15,744,777	15,431,328
Cash dividends declared	$ 1.21	$ 0.94
Fiduciary and Trust [Member]
Noninterest Income [Abstract]
Revenue from Contract with Customer, Including Assessed Tax	$ 6,723,000	$ 6,395,000
Deposit Account [Member]
Noninterest Income [Abstract]
Revenue from Contract with Customer, Including Assessed Tax	2,559,000	2,922,000
Bank Servicing [Member]
Noninterest Income [Abstract]
Revenue from Contract with Customer, Including Assessed Tax	$ 2,818,000	$ 4,172,000