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:
Loans, including fees	$ 866,358	$ 924,639	$ 1,019,036
Investment securities available for sale	52,567	67,281	107,435
Trading account assets	548	963	925
Mortgage loans held for sale	4,441	6,201	6,195
Federal Reserve Bank balances	3,222	3,451	6,660
Other earning assets	1,878	1,605	1,505
Total interest income	929,014	1,004,140	1,141,756
Interest expense:
Deposits	64,392	95,749	173,885
Federal funds purchased and securities sold under repurchase agreements	324	614	1,063
Long-term debt	54,106	53,660	42,654
Total interest expense	118,822	150,023	217,602
Net interest income	810,192	854,117	924,154
Provision for loan losses	69,598	320,369	418,795
Net interest income after provision for loan losses	740,594	533,748	505,359
Non-interest income:
Service charges on deposit accounts	77,789	78,203	78,770
Fiduciary and asset management fees	43,450	42,503	45,809
Brokerage revenue	27,538	26,913	26,006
Mortgage banking income	22,482	32,272	20,316
Bankcard fees	30,641	34,075	41,493
Investment securities gains, net	2,945	39,142	75,007
Other fee income	22,567	21,138	19,953
Decrease (increase) in fair value of private equity investments, net	(2,963)	8,233	(1,118)
Other non-interest income	29,122	31,487	32,638
Total non-interest income	253,571	313,966	338,874
Non-interest expense:
Salaries and other personnel expense	368,152	375,872	371,546
Net occupancy and equipment expense	103,339	105,575	114,037
FDIC insurance and other regulatory fees	32,758	45,408	59,063
Foreclosed real estate expense, net	33,864	90,655	133,570
Loss (gain) on sale of other loans held for sale, net	329	4,681	(2,737)
Professional fees	38,776	41,307	40,585
Third-party services	40,135	38,006	40,028
Visa indemnification charge (recovery)	1,600	6,304	6,038
Restructuring charges	11,064	5,412	30,665
Other operating expenses	111,520	103,017	110,970
Total non-interest expense	741,537	816,237	903,765
Income (loss) before income taxes	252,628	31,477	(59,532)
Income tax expense (benefit)	93,245	(798,732)	1,312
Net income (loss)	159,383	830,209	(60,844)
Net (loss) income available to non-controlling interest	0	0	(220)
Net loss attributable to controlling interest	159,383	830,209	(60,624)
Dividends and accretion of discount on preferred stock	40,830	58,703	58,088
Net loss attributable to common shareholders	$ 118,553	$ 771,506	$ (118,712)
Net income (loss) per common share, basic (per share)	$ 0.13	$ 0.98	$ (0.15)
Net income (loss) per common share, diluted (per share)	$ 0.13	$ 0.85	$ (0.15)
Weighted average common shares outstanding, basic	892,462	786,466	785,272
Weighted average common shares outstanding, diluted	939,580	910,102	785,272