Loans and Allowance for Credit Losses Past Due Loan Status and Non-Accrual Loans by Portfolio Segment (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
31-59 Days Past Due	$ 62,810	$ 62,895
60-89 Days Past Due	43,583	36,435
>90 Days Past Due and Accruing	28,767	48,084
Non-accrual	257,761	280,688
Total >90 Days	286,528	328,772
Total Past Due	392,921	428,102
Current	11,576,049	11,505,205
Loans, net of unearned income	11,968,970	11,933,307
Commercial - industrial, financial, and agricultural
31-59 Days Past Due	9,955	5,903
60-89 Days Past Due	5,013	7,390
>90 Days Past Due and Accruing	5,240	14,105
Non-accrual	75,704	73,350
Total >90 Days	80,944	87,455
Total Past Due	95,912	100,748
Current	3,543,456	3,603,636
Loans, net of unearned income	3,639,368	3,704,384
Real-estate commercial mortage
31-59 Days Past Due	11,167	15,898
60-89 Days Past Due	14,437	8,491
>90 Days Past Due and Accruing	4,394	6,744
Non-accrual	109,412	86,976
Total >90 Days	113,806	93,720
Total Past Due	139,410	118,109
Current	4,463,186	4,257,871
Loans, net of unearned income	4,602,596	4,375,980
Commercial - Secured [Member]
31-59 Days Past Due	9,284	5,274
60-89 Days Past Due	4,498	6,837
>90 Days Past Due and Accruing	4,831	13,374
Non-accrual	73,048	72,162
Total >90 Days	77,879	85,536
Total Past Due	91,661	97,647
Current	3,301,899	3,373,651
Loans, net of unearned income	3,393,560	3,471,298
Commercial - Unsecured [Member]
31-59 Days Past Due	671	629
60-89 Days Past Due	515	553
>90 Days Past Due and Accruing	409	731
Non-accrual	2,656	1,188
Total >90 Days	3,065	1,919
Total Past Due	4,251	3,101
Current	241,557	229,985
Loans, net of unearned income	245,808	233,086
Real-estate - home equity
31-59 Days Past Due	7,439	8,138
60-89 Days Past Due	4,194	3,767
>90 Days Past Due and Accruing	5,714	10,024
Non-accrual	5,493	164
Total >90 Days	11,207	10,188
Total Past Due	22,840	22,093
Current	1,601,722	1,619,684
Loans, net of unearned income	1,624,562	1,641,777
Real-estate - residential mortgage
31-59 Days Past Due	23,877	24,237
60-89 Days Past Due	13,246	12,094
>90 Days Past Due and Accruing	8,502	13,346
Non-accrual	7,834	37,066
Total >90 Days	16,336	50,412
Total Past Due	53,459	86,743
Current	1,043,733	909,247
Loans, net of unearned income	1,097,192	995,990
Real-estate - construction
31-59 Days Past Due	4,744	3,872
60-89 Days Past Due	4,824	3,401
>90 Days Past Due and Accruing	1,850	1,570
Non-accrual	58,894	83,046
Total >90 Days	60,744	84,616
Total Past Due	70,312	91,889
Current	545,133	709,296
Loans, net of unearned income	615,445	801,185
Construction - Commercial Residential [Member]
31-59 Days Past Due	2,372	3,872
60-89 Days Past Due	4,824	3,401
>90 Days Past Due and Accruing	1,656	884
Non-accrual	53,420	75,552
Total >90 Days	55,076	76,436
Total Past Due	62,272	83,709
Current	290,665	409,190
Loans, net of unearned income	352,937	492,899
Construction - Commercial [Member]
31-59 Days Past Due	31	0
60-89 Days Past Due	0	0
>90 Days Past Due and Accruing	128	195
Non-accrual	4,347	5,092
Total >90 Days	4,475	5,287
Total Past Due	4,506	5,287
Current	204,875	239,150
Loans, net of unearned income	209,381	244,437
Construction other [Member]
31-59 Days Past Due	2,341	0
60-89 Days Past Due	0	0
>90 Days Past Due and Accruing	66	491
Non-accrual	1,127	2,402
Total >90 Days	1,193	2,893
Total Past Due	3,534	2,893
Current	49,593	60,956
Loans, net of unearned income	53,127	63,849
Consumer
31-59 Days Past Due	4,703	4,374
60-89 Days Past Due	1,745	1,249
>90 Days Past Due and Accruing	3,016	2,140
Non-accrual	368	14
Total >90 Days	3,384	2,154
Total Past Due	9,832	7,777
Current	308,269	342,384
Loans, net of unearned income	318,101	350,161
Consumer - Direct [Member]
31-59 Days Past Due	455	707
60-89 Days Past Due	202	228
>90 Days Past Due and Accruing	150	212
Non-accrual	368	0
Total >90 Days	518	212
Total Past Due	1,175	1,147
Current	34,263	45,942
Loans, net of unearned income	35,438	47,089
Consumer - Indirect [Member]
31-59 Days Past Due	1,997	1,916
60-89 Days Past Due	440	359
>90 Days Past Due and Accruing	183	290
Non-accrual	0	0
Total >90 Days	183	290
Total Past Due	2,620	2,565
Current	151,112	166,531
Loans, net of unearned income	153,732	169,096
Consumer Other [Member]
31-59 Days Past Due	2,251	1,751
60-89 Days Past Due	1,103	662
>90 Days Past Due and Accruing	2,683	1,638
Non-accrual	0	14
Total >90 Days	2,683	1,652
Total Past Due	6,037	4,065
Current	122,894	129,911
Loans, net of unearned income	128,931	133,976
Finance Leases Portfolio Segment [Member]
31-59 Days Past Due	925	473
60-89 Days Past Due	124	43
>90 Days Past Due and Accruing	51	155
Non-accrual	56	72
Total >90 Days	107	227
Total Past Due	1,156	743
Current	70,550	63,087
Loans, net of unearned income	71,706	63,830
Subtotal [Member]
Loans, net of unearned income		$ 11,933,307