Consolidated Statements Of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Interest income:
Interest and fees on loans	$ 1,814,600	$ 1,889,884	$ 2,049,928
Interest on money market investments	23,363	21,080	13,832
Interest on securities:
Held-to-maturity	31,280	34,751	35,716
Available-for-sale	71,107	92,261	87,105
Trading account	1,055	746	2,000
Total interest income	1,941,405	2,038,722	2,188,581
Interest expense:
Interest on deposits	58,913	80,146	128,479
Interest on short-term borrowings	313	1,406	6,685
Interest on long-term debt	185,851	225,230	297,232
Total interest expense	245,077	306,782	432,396
Net interest income	1,696,328	1,731,940	1,756,185
Provision for loan losses	(87,136)	14,227	74,532
Net interest income after provision for loan losses	1,783,464	1,717,713	1,681,653
Noninterest income:
Service charges and fees on deposit accounts	176,339	176,401	174,435
Other service charges, commissions and fees	181,473	174,420	185,836
Trust and wealth management income	29,913	28,402	26,683
Capital markets and foreign exchange	28,051	26,810	31,407
Dividends and other investment income	46,062	55,825	42,428
Loan sales and servicing income	35,293	39,929	28,072
Fair value and nonhedge derivative loss	(18,152)	(21,782)	(4,980)
Equity securities gains, net	8,520	11,253	6,511
Fixed income securities gains (losses), net	(2,898)	19,544	11,868
Impairment losses on investment securities:
Impairment losses on investment securities	(188,606)	(166,257)	(77,325)
Noncredit-related losses on securities not expected to be sold (recognized in other comprehensive income)	23,472	62,196	43,642
Net impairment losses on investment securities	(165,134)	(104,061)	(33,683)
Other	17,940	13,129	29,607
Total noninterest income	337,407	419,870	498,184
Noninterest expense:
Salaries and employee benefits	912,918	885,661	874,293
Occupancy, net	112,303	112,947	112,537
Furniture, equipment, and software	106,629	108,990	105,703
Other real estate expense	1,712	19,723	77,570
Credit-related expense	33,653	50,518	61,629
Provision for unfunded lending commitments	(17,104)	4,387	(9,286)
Legal and professional services	67,968	52,509	38,992
Advertising	23,362	25,720	27,164
FDIC premiums	38,019	43,401	63,918
Amortization of core deposit and other intangibles	14,375	17,010	20,070
Debt extinguishment cost	120,192	0	0
Other	300,412	275,151	285,974
Total noninterest expense	1,714,439	1,596,017	1,658,564
Income before income taxes	406,432	541,566	521,273
Income taxes	142,977	193,416	198,583
Net income	263,455	348,150	322,690
Net loss applicable to noncontrolling interests	(336)	(1,366)	(1,114)
Net income applicable to controlling interest	263,791	349,516	323,804
Preferred stock dividends	(95,512)	(170,885)	(170,414)
Preferred stock redemption	125,700	0	0
Net earnings applicable to common shareholders	$ 293,979	$ 178,631	$ 153,390
Weighted average common shares outstanding during the period:
Basic shares	183,844	183,081	182,393
Diluted shares	184,297	183,236	182,605
Net earnings per common share:
Basic, per share	$ 1.58	$ 0.97	$ 0.83
Diluted, per share	$ 1.58	$ 0.97	$ 0.83