CONSOLIDATED STATEMENTS OF INCOME (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Interest Income:
Interest and fees on loans and leases	$ 123,369,000	$ 122,380,000	$ 115,574,000
Interest on loans held for sale	312,000	929,000	841,000
Interest on deposits with banks	85,000	84,000	111,000
Interest and dividends on investment securities:
Taxable	15,377,000	16,635,000	17,951,000
Exempt from federal income taxes	9,222,000	9,318,000	9,392,000
Interest on federal funds sold	1,000	1,000	1,000
Total interest income	148,366,000	149,347,000	143,870,000
Interest Expense:
Interest on deposits	4,791,000	5,439,000	7,357,000
Interest on retail repurchase agreements and federal funds purchased	164,000	163,000	204,000
Interest on advances from FHLB	12,982,000	12,936,000	14,131,000
Interest on subordinated debt	881,000	895,000	959,000
Total interest expense	18,818,000	19,433,000	22,651,000
Net interest income	129,548,000	129,914,000	121,219,000
Provision (credit) for loan and lease losses	(163,000)	(1,084,000)	3,649,000
Net interest income after provision (credit) for loan and lease losses	129,711,000	130,998,000	117,570,000
Non-interest Income:
Investment securities gains	5,000	115,000	459,000
Total other-than-temporary impairment ("OTTI") losses	0	0	(109,000)
Portion of OTTI losses recognized in other comprehensive income, before taxes	0	0	0
Net OTTI recognized in earnings	0	0	(109,000)
Service charges on deposit accounts	8,422,000	8,533,000	8,910,000
Mortgage banking activities	1,994,000	3,094,000	6,032,000
Wealth management income	19,086,000	17,585,000	15,949,000
Insurance agency commissions	4,996,000	4,821,000	4,490,000
Income from bank owned life insurance	2,444,000	2,499,000	2,616,000
Visa check fees	4,439,000	4,165,000	3,887,000
Other income	5,485,000	6,699,000	4,722,000
Total non-interest income	46,871,000	47,511,000	46,956,000
Non-interest Expenses:
Salaries and employee benefits	66,387,000	65,598,000	62,509,000
Occupancy expense of premises	13,692,000	13,171,000	12,010,000
Equipment expenses	5,188,000	4,940,000	4,871,000
Marketing	2,926,000	2,880,000	2,651,000
Outside data services	4,947,000	4,580,000	5,019,000
FDIC insurance	2,302,000	2,300,000	2,573,000
Amortization of intangible assets	821,000	1,845,000	1,881,000
Litigation Expense	6,519,000	0	0
Other Expense	18,018,000	16,210,000	18,413,000
Total non-interest expenses	120,800,000	111,524,000	109,927,000
Income before income taxes	55,782,000	66,985,000	54,599,000
Income tax expense	17,582,000	22,563,000	18,045,000
Net income	$ 38,200,000	$ 44,422,000	$ 36,554,000
Net Income Per Share Amounts:
Basic net income per share	$ 1.53	$ 1.78	$ 1.49
Diluted net income per share	$ 1.52	$ 1.77	$ 1.48
Dividends declared per share	$ 0.76	$ 0.64	$ 0.48