Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Interest income:
Loans, including fees	$ 103,316	$ 98,336	$ 205,372	$ 195,687
Securities:
Taxable	25,485	34,399	52,862	70,465
Tax-exempt	28,690	22,125	56,644	44,628
Interest-bearing deposits	1,498	903	2,851	1,833
Federal funds sold and resell agreements	29	33	51	48
Total interest income	159,018	155,796	317,780	312,661
Interest expense:
Deposits	3,882	4,547	7,890	9,119
Federal funds purchased and repurchase agreements	29	34	59	68
Junior subordinated deferrable interest debentures	1,690	1,711	3,363	3,385
Other long-term borrowings	236	287	474	1,165
Total interest expense	5,837	6,579	11,786	13,737
Net interest income	153,181	149,217	305,994	298,924
Provision for loan losses	3,575	2,355	9,575	3,455
Net interest income after provision for loan losses	149,606	146,862	296,419	295,469
Non-interest income:
Trust and investment management fees	22,561	21,279	44,446	41,931
Service charges on deposit accounts	20,044	20,639	40,088	41,433
Insurance commissions and fees	9,266	9,171	22,336	21,548
Interchange and debit card transaction fees	4,268	4,292	8,279	8,409
Other charges, commissions and fees	8,578	7,825	16,333	15,175
Net gain (loss) on securities transactions	6	370	11	(121)
Other	7,786	6,187	18,796	13,367
Total non-interest income	72,509	69,763	150,289	141,742
Non-interest expense:
Salaries and wages	66,502	62,624	132,967	126,326
Employee benefits	14,629	14,048	32,620	30,749
Net occupancy	12,645	12,213	24,624	24,010
Furniture and equipment	14,986	13,734	29,171	27,154
Deposit insurance	2,835	2,838	5,724	5,335
Intangible amortization	788	994	1,608	2,005
Other	37,373	36,085	78,858	68,997
Total non-interest expense	149,758	142,536	305,572	284,576
Income before income taxes	72,357	74,089	141,136	152,635
Income taxes	12,694	16,027	26,285	33,540
Net income	59,663	58,062	114,851	119,095
Preferred stock dividends	2,688		2,688
Net income available to common shareholders	$ 56,975	$ 58,062	$ 112,163	$ 119,095
Earnings per common share:
Basic	$ 0.95	$ 0.94	$ 1.86	$ 1.94
Diluted	$ 0.94	$ 0.94	$ 1.85	$ 1.93