Consolidated Statements Of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Interest income:
Interest and fees on loans	$ 479,199	$ 520,133	$ 1,444,383	$ 1,562,031
Interest on money market investments	5,349	3,482	15,076	9,524
Interest on securities:
Held-to-maturity	8,337	8,937	26,621	26,610
Available-for-sale	22,042	21,382	70,290	65,837
Trading account	110	462	596	1,452
Total interest income	515,037	554,396	1,556,966	1,665,454
Interest expense:
Interest on deposits	19,049	31,093	63,285	101,834
Interest on short-term borrowings	193	1,501	1,228	5,464
Interest on long-term debt	51,597	51,207	173,969	247,533
Total interest expense	70,839	83,801	238,482	354,831
Net interest income	444,198	470,595	1,318,484	1,310,623
Provision for loan losses	(1,889)	14,553	24,628	75,883
Net interest income after provision for loan losses	446,087	456,042	1,293,856	1,234,740
Noninterest income:
Service charges and fees on deposit accounts	44,951	44,154	131,909	131,562
Other service charges, commissions and fees	38,642	45,308	111,422	130,951
Trust and wealth management income	6,521	6,269	20,952	20,202
Capital markets and foreign exchange	6,026	7,729	19,102	23,301
Dividends and other investment income	11,686	9,356	42,708	34,623
Loan sales and servicing income	10,695	6,165	29,334	22,014
Fair value and nonhedge derivative income (loss)	(5,820)	(5,718)	(17,004)	(303)
Equity securities gains, net	2,683	5,289	11,935	4,550
Fixed income securities gains (losses), net	3,046	13,035	9,285	10,580
Impairment losses on investment securities:
Impairment losses on investment securities	(3,876)	(55,530)	(46,175)	(64,974)
Noncredit-related losses on securities not expected to be sold (recognized in other comprehensive income)	1,140	42,196	25,922	43,377
Net impairment losses on investment securities	(2,736)	(13,334)	(20,253)	(21,597)
Other	3,495	2,789	9,820	27,651
Total noninterest income	119,189	121,042	349,210	383,534
Noninterest expense:
Salaries and employee benefits	220,223	216,855	665,622	654,003
Occupancy, net	28,601	29,040	84,721	84,638
Furniture and equipment	27,122	26,852	81,216	78,667
Other real estate expense	207	20,564	14,457	62,634
Credit-related expense	13,316	15,379	39,216	47,416
Provision for unfunded lending commitments	2,264	(2,202)	3,428	(13,646)
Legal and professional services	12,749	8,897	36,792	24,018
Advertising	7,326	6,511	19,751	19,384
FDIC premiums	11,278	12,573	32,641	51,906
Amortization of core deposit and other intangibles	4,241	4,773	12,794	15,329
Other	67,648	69,776	198,365	209,300
Total noninterest expense	394,975	409,018	1,189,003	1,233,649
Income before income taxes	170,301	168,066	454,063	384,625
Income taxes	60,704	59,348	163,599	150,706
Net income	109,597	108,718	290,464	233,919
Net loss applicable to noncontrolling interests	(254)	(375)	(800)	(866)
Net income applicable to controlling interest	109,851	109,093	291,264	234,785
Preferred stock dividends	(47,529)	(43,928)	(148,238)	(125,815)
Net earnings applicable to common shareholders	$ 62,322	$ 65,165	$ 143,026	$ 108,970
Weighted average common shares outstanding during the period:
Basic shares	183,237	182,676	183,008	182,289
Diluted shares	183,383	183,858	183,162	182,531
Net earnings per common share:
Basic, per share	$ 0.34	$ 0.35	$ 0.77	$ 0.59
Diluted, per share	$ 0.34	$ 0.35	$ 0.77	$ 0.59