Fair Value (Schedule Of Carrying Values And Estimated Fair Values Of Financial Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Fair Value, Estimate Not Practicable, Financial Statement Captions [Line Items]
HTM investment securities	$ 715,710	$ 729,974
Time deposits	3,211,942	3,413,550
Other short-term borrowings	7,621	70,273
Long-term debt (less fair value hedges)	2,274,571	1,954,462
Carrying Value [Member]
Fair Value, Estimate Not Practicable, Financial Statement Captions [Line Items]
HTM investment securities	773,016	807,804
Loans and leases (including loans held for sale), net of allowance	36,040,879	36,296,284
Time deposits	3,211,942	3,413,550
Foreign deposits	1,504,827	1,575,361
Other short-term borrowings	7,621	70,273
Long-term debt (less fair value hedges)	2,265,233	1,943,618
Estimated Fair Value [Member]
Fair Value, Estimate Not Practicable, Financial Statement Captions [Line Items]
HTM investment securities	715,710	729,974
Loans and leases (including loans held for sale), net of allowance	36,116,562	36,006,619
Time deposits	3,240,712	3,444,189
Foreign deposits	1,504,178	1,574,271
Other short-term borrowings	7,655	70,387
Long-term debt (less fair value hedges)	$ 2,560,106	$ 2,225,078