Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Interest Income
Loans, including fees	$ 543,385	$ 524,060	$ 530,308
Investment securities:
Taxable	44,975	45,279	50,651
Tax-exempt	9,662	7,879	8,977
Dividends	571	985	1,338
Loans held for sale	728	801	786
Other interest income	3,779	4,785	4,018
Total Interest Income	603,100	583,789	596,078
Interest Expense
Deposits	44,693	40,482	35,110
Short-term borrowings	855	372	1,608
Long-term debt	36,780	42,941	44,493
Total Interest Expense	82,328	83,795	81,211
Net Interest Income	520,772	499,994	514,867
Provision for credit losses	13,182	2,250	12,500
Net Interest Income After Provision for Credit Losses	507,590	497,744	502,367
Non-Interest Income
Service charges on deposit accounts	51,346	50,097	49,293
Investment management and trust services	45,270	44,056	44,605
Other service charges and fees	51,473	43,992	39,896
Mortgage banking income	19,415	18,208	17,107
Other	20,124	16,420	14,437
Investment securities gains (losses):
Net gains on sales of investment securities	2,550	9,066	2,071
Net other-than-temporary impairment losses	0	0	(30)
Investment securities gains, net	2,550	9,066	2,041
Total Non-Interest Income	190,178	181,839	167,379
Non-Interest Expense
Salaries and employee benefits	283,353	260,832	251,021
Net occupancy expense	47,611	47,777	48,130
Other outside services	23,883	27,785	28,404
Data processing	20,016	19,894	17,162
Software	16,903	14,746	12,758
Equipment expense	12,788	14,514	13,567
Professional fees	11,004	11,244	12,097
FDIC insurance expense	9,767	11,470	10,958
Marketing	7,044	7,324	8,133
Telecommunications	5,702	6,350	6,870
Supplies and postage	10,292	10,202	9,795
Operating risk loss	2,815	3,624	4,271
Other real estate owned and repossession expense	1,926	3,630	3,270
Loss on redemption of trust preferred securities	0	5,626	0
Intangible amortization	0	247	1,259
Other	36,415	34,895	31,551
Total Non-Interest Expense	489,519	480,160	459,246
Income Before Income Taxes	208,249	199,423	210,500
Income taxes	46,624	49,921	52,606
Net Income	$ 161,625	$ 149,502	$ 157,894
PER COMMON SHARE:
Net Income (Basic) (usd per share)	$ 0.93	$ 0.85	$ 0.85
Net Income (Diluted) (usd per share)	0.93	0.85	0.84
Cash Dividends (usd per share)	$ 0.41	$ 0.38	$ 0.34