Loans and leases and the allowance for credit losses (Details 1) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Summary of current, past due and nonaccrual loans
Current	$ 55,575,513	$ 49,739,383
30-89 days past due	580,566	645,193
90 days or more past due and accruing	373,197	269,593
Purchased impaired	752,978	97,019
Nonaccrual	1,258,975	1,239,194
Loans and leases, net of unearned discount	58,541,229	51,990,382
Purchased Impaired [Member]
Summary of current, past due and nonaccrual loans
Loans and leases, net of unearned discount	752,978	97,019
Purchased Impaired [Member] | Commercial, financial, leasing [Member]
Summary of current, past due and nonaccrual loans
Loans and leases, net of unearned discount	37,773	2,250
Commercial, financial, leasing [Member]
Summary of current, past due and nonaccrual loans
Current	14,791,110	13,088,887
30-89 days past due	24,900	96,087
90 days or more past due and accruing	23,488	16,647
Purchased impaired	37,773	2,250
Nonaccrual	163,621	186,739
Loans and leases, net of unearned discount	15,040,892	13,390,610
Commercial Real Estate Excluding Residential Builder and Developer and Other Construction [Member]
Summary of current, past due and nonaccrual loans
Current	18,900,107	16,589,240
30-89 days past due	104,668	89,906
90 days or more past due and accruing	85,938	35,338
Purchased impaired	226,083	8,275
Nonaccrual	234,171	209,031
Loans and leases, net of unearned discount	19,550,967	16,931,790
Residential builder and developer [Member]
Summary of current, past due and nonaccrual loans
Current	1,047,647	891,764
30-89 days past due	39,246	30,805
90 days or more past due and accruing	28,606	9,763
Purchased impaired	366,879	72,710
Nonaccrual	359,152	346,448
Loans and leases, net of unearned discount	1,841,530	1,351,490
Other commercial construction [Member]
Summary of current, past due and nonaccrual loans
Current	2,635,409	2,723,399
30-89 days past due	37,360	36,420
90 days or more past due and accruing	32,173	11,323
Purchased impaired	51,435	2,098
Nonaccrual	114,852	126,641
Loans and leases, net of unearned discount	2,871,229	2,899,881
Residential real estate excluding Alt-A [Member]
Summary of current, past due and nonaccrual loans
Current	5,737,580	4,699,711
30-89 days past due	211,506	229,641
90 days or more past due and accruing	199,109	192,276
Purchased impaired	64,327	9,320
Nonaccrual	187,471	172,729
Loans and leases, net of unearned discount	6,399,993	5,303,677
Residential Alt-A [Member]
Summary of current, past due and nonaccrual loans
Current	426,437	475,236
30-89 days past due	37,050	42,674
90 days or more past due and accruing	0	0
Purchased impaired	0	0
Nonaccrual	107,441	106,469
Loans and leases, net of unearned discount	570,928	624,379
Home equity lines and loans [Member]
Summary of current, past due and nonaccrual loans
Current	6,740,046	6,472,563
30-89 days past due	37,438	38,367
90 days or more past due and accruing	0	0
Purchased impaired	5,097	2,366
Nonaccrual	49,941	43,055
Loans and leases, net of unearned discount	6,832,522	6,556,351
Automobile [Member]
Summary of current, past due and nonaccrual loans
Current	2,767,206	2,608,230
30-89 days past due	49,518	44,604
90 days or more past due and accruing	0	0
Purchased impaired	0	0
Nonaccrual	27,724	31,892
Loans and leases, net of unearned discount	2,844,448	2,684,726
Other [Member]
Summary of current, past due and nonaccrual loans
Current	2,529,971	2,190,353
30-89 days past due	38,880	36,689
90 days or more past due and accruing	3,883	4,246
Purchased impaired	1,384	0
Nonaccrual	14,602	16,190
Loans and leases, net of unearned discount	$ 2,588,720	$ 2,247,478