Loans And Allowance For Loan Losses (Aging Information On Past Due And Accruing Loans) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Loans And Allowance For Loan Losses [Line Items]
Current or Less Than 30 Days Past Due	$ 11,351,005	$ 10,839,081
30 - 89 Days Past Due	54,145	54,975
90 Days Past Due and Still Accruing	11,629	13,966
Non-accrual	43,260	48,814
Total	11,460,039	10,956,836
Business [Member] | Commercial Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Current or Less Than 30 Days Past Due	4,077,664	3,697,589
30 - 89 Days Past Due	5,873	5,467
90 Days Past Due and Still Accruing	623	671
Non-accrual	11,093	11,592
Total	4,095,253	3,715,319
Real Estate - Construction And Land [Member] | Commercial Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Current or Less Than 30 Days Past Due	423,589	386,423
30 - 89 Days Past Due	10,031	9,601
90 Days Past Due and Still Accruing	275	0
Non-accrual	8,198	10,173
Total	442,093	406,197
Real Estate - Business [Member] | Commercial Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Current or Less Than 30 Days Past Due	2,256,513	2,292,385
30 - 89 Days Past Due	4,911	1,340
90 Days Past Due and Still Accruing	0	47
Non-accrual	16,474	19,778
Total	2,277,898	2,313,550
Real Estate - Personal [Member] | Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Current or Less Than 30 Days Past Due	1,802,553	1,771,231
30 - 89 Days Past Due	9,559	9,755
90 Days Past Due and Still Accruing	1,235	1,560
Non-accrual	5,857	5,080
Total	1,819,204	1,787,626
Consumer [Member] | Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Current or Less Than 30 Days Past Due	1,621,468	1,492,960
30 - 89 Days Past Due	13,377	17,482
90 Days Past Due and Still Accruing	1,358	2,274
Non-accrual	1,638	0
Total	1,637,841	1,512,716
Revolving Home Equity [Member] | Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Current or Less Than 30 Days Past Due	421,186	416,614
30 - 89 Days Past Due	1,465	1,082
90 Days Past Due and Still Accruing	915	702
Non-accrual	0	2,191
Total	423,566	420,589
Consumer Credit Card [Member] | Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Current or Less Than 30 Days Past Due	744,410	777,564
30 - 89 Days Past Due	8,656	9,952
90 Days Past Due and Still Accruing	7,223	8,712
Non-accrual	0	0
Total	760,289	796,228
Overdrafts [Member] | Personal Banking Portfolio Segment [Member]
Loans And Allowance For Loan Losses [Line Items]
Current or Less Than 30 Days Past Due	3,622	4,315
30 - 89 Days Past Due	273	296
90 Days Past Due and Still Accruing	0	0
Non-accrual	0	0
Total	$ 3,895	$ 4,611