Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Interest income:
Loans, including fees	$ 102,056	$ 97,351
Securities:
Taxable	27,377	36,066
Tax-exempt	27,954	22,503
Interest-bearing deposits	1,353	930
Federal funds sold and resell agreements	22	15
Total interest income	158,762	156,865
Interest expense:
Deposits	4,008	4,572
Federal funds purchased and repurchase agreements	30	34
Junior subordinated deferrable interest debentures	1,673	1,674
Other long-term borrowings	238	878
Total interest expense	5,949	7,158
Net interest income	152,813	149,707
Provision for loan losses	6,000	1,100
Net interest income after provision for loan losses	146,813	148,607
Non-interest income:
Trust and investment management fees	21,885	20,652
Service charges on deposit accounts	20,044	20,794
Insurance commissions and fees	13,070	12,377
Interchange and debit card transaction fees	4,011	4,117
Other charges, commissions and fees	7,755	7,350
Net gain (loss) on securities transactions	5	(491)
Other	11,010	7,180
Total non-interest income	77,780	71,979
Non-interest expense:
Salaries and wages	66,465	63,702
Employee benefits	17,991	16,701
Net occupancy	11,979	11,797
Furniture and equipment	14,185	13,420
Deposit insurance	2,889	2,497
Intangible amortization	820	1,011
Other	41,485	32,912
Total non-interest expense	155,814	142,040
Income before income taxes	68,779	78,546
Income taxes	13,591	17,513
Net income	55,188	61,033
Preferred stock dividends and accretion	137
Net income available to common shareholders	$ 55,051	$ 61,033
Earnings per common share:
Basic	$ 0.91	$ 0.99
Diluted	$ 0.91	$ 0.99