Loans (Schedule Of Allowance For Loan Losses By Portfolio Segment And Based On Impairment) (Details) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Loans individually evaluated for impairment, Allowance	$ 14,264	$ 13,116
Loans individually evaluated for impairment, Balance	374,383	366,740
Loans collectively evaluated for impairment, Allowance	215,636	232,115
Loans collectively evaluated for impairment, Balance	6,547,774	6,501,881
Total allowance	229,900	245,231
Total balance	6,922,157	6,868,621
Commercial Loans [Member]
Loans individually evaluated for impairment, Allowance	2,482	2,540
Loans individually evaluated for impairment, Balance	50,440	33,555
Loans collectively evaluated for impairment, Allowance	63,378	61,379
Loans collectively evaluated for impairment, Balance	1,586,692	1,407,612
Total allowance	65,860	63,919
Total balance	1,637,132	1,441,167
Real Estate Construction Loans [Member]
Loans individually evaluated for impairment, Allowance	7,140	7,470
Loans individually evaluated for impairment, Balance	76,969	77,691
Loans collectively evaluated for impairment, Allowance	30,543	35,791
Loans collectively evaluated for impairment, Balance	231,970	332,295
Total allowance	37,683	43,261
Total balance	308,939	409,986
Commercial Mortgage Loans [Member]
Loans individually evaluated for impairment, Allowance	3,481	3,106
Loans individually evaluated for impairment, Balance	229,043	248,059
Loans collectively evaluated for impairment, Allowance	113,533	125,241
Loans collectively evaluated for impairment, Balance	3,575,482	3,692,002
Total allowance	117,014	128,347
Total balance	3,804,525	3,940,061
Residential Mortgage And Equity Lines [Member]
Loans individually evaluated for impairment, Allowance	1,161
Loans individually evaluated for impairment, Balance	17,931	7,435
Loans collectively evaluated for impairment, Allowance	8,146	9,668
Loans collectively evaluated for impairment, Balance	1,137,513	1,053,895
Total allowance	9,307	9,668
Total balance	1,155,444	1,061,330
Consumer And Other [Member]
Loans collectively evaluated for impairment, Allowance	36	36
Loans collectively evaluated for impairment, Balance	16,117	16,077
Total allowance	36	36
Total balance	$ 16,117	$ 16,077