Credit Quality (Summary Of Age Analysis Of Past Due Loans By Class) (Details) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	$ 44,417	$ 43,622
>90 Days Past Due and Still Accruing	16,610	8,634
Non-Accrual	113,416	115,589
Total Past Due	174,443	167,845
Current	6,614,097	5,920,310
Total Loans	6,788,540	6,088,155
Commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	17,139	17,101
>90 Days Past Due and Still Accruing	9,604	3,020
Non-Accrual	103,101	106,724
Total Past Due	129,844	126,845
Current	3,689,962	3,211,147
Total Loans	3,819,806	3,337,992
Direct Installment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	8,692	8,603
>90 Days Past Due and Still Accruing	2,709	2,496
Non-Accrual	3,435	3,285
Total Past Due	14,836	14,384
Current	1,018,852	988,341
Total Loans	1,033,688	1,002,725
Residential Mortgages [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	11,593	9,127
>90 Days Past Due and Still Accruing	3,723	2,144
Non-Accrual	3,577	3,272
Total Past Due	18,893	14,543
Current	654,705	607,699
Total Loans	673,598	622,242
Indirect Installment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	3,668	5,659
>90 Days Past Due and Still Accruing	300	394
Non-Accrual	899	750
Total Past Due	4,867	6,803
Current	533,499	507,566
Total Loans	538,366	514,369
Consumer Lines Of Credit [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	2,303	1,581
>90 Days Past Due and Still Accruing	260	571
Non-Accrual	1,054	588
Total Past Due	3,617	2,740
Current	577,351	491,141
Total Loans	580,968	493,881
Commercial Leases [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	1,021	1,551
>90 Days Past Due and Still Accruing		9
Non-Accrual	1,350	970
Total Past Due	2,371	2,530
Current	101,393	76,899
Total Loans	103,764	79,429
Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	1
>90 Days Past Due and Still Accruing	14
Total Past Due	15
Current	38,335	37,517
Total Loans	$ 38,350	$ 37,517