Loans (Schedule Of Aging Of Loan Portfolio) (Details) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
30-59 Days Past Due	$ 16,412	$ 44,174
60-89 Days Past Due	27,066	30,426
Greater than 90 Days Past Due		5,006
Non-accrual Loans	256,419	242,319
Total Past Due	299,897	321,925
Loans Not Past Due	6,622,260	6,546,696
Loans and Leases Receivable, Gross, Carrying Amount	6,922,157	6,868,621
Commercial Loans [Member]
30-59 Days Past Due	360	7,037
60-89 Days Past Due	11,920	2,990
Non-accrual Loans	34,350	31,498
Total Past Due	46,630	41,525
Loans Not Past Due	1,590,502	1,399,642
Loans and Leases Receivable, Gross, Carrying Amount	1,637,132	1,441,167
Real Estate Construction Loans [Member]
30-59 Days Past Due	1,200	14,634
60-89 Days Past Due	1,709	15,425
Greater than 90 Days Past Due		4,175
Non-accrual Loans	70,449	53,937
Total Past Due	73,358	88,171
Loans Not Past Due	235,581	321,815
Loans and Leases Receivable, Gross, Carrying Amount	308,939	409,986
Commercial Mortgage Loans [Member]
30-59 Days Past Due	13,969	12,569
60-89 Days Past Due	12,235	9,430
Greater than 90 Days Past Due		831
Non-accrual Loans	136,301	144,596
Total Past Due	162,505	167,426
Loans Not Past Due	3,642,020	3,772,635
Loans and Leases Receivable, Gross, Carrying Amount	3,804,525	3,940,061
Residential Mortgage And Equity Lines [Member]
30-59 Days Past Due	828	9,934
60-89 Days Past Due	1,202	2,581
Non-accrual Loans	15,319	12,288
Total Past Due	17,349	24,803
Loans Not Past Due	1,138,095	1,036,527
Loans and Leases Receivable, Gross, Carrying Amount	1,155,444	1,061,330
Installment And Other Loans [Member]
30-59 Days Past Due	55
Total Past Due	55
Loans Not Past Due	16,062	16,077
Loans and Leases Receivable, Gross, Carrying Amount	$ 16,117	$ 16,077