Loans And Allowance For Loan Losses (Schedule Of Current, Accruing Past Due And Nonaccrual Loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	$ 22,243,382	$ 20,879,481
Accruing 30-89 Days Past Due	45,291	46,614
Accruing 90 Days or Greater Past Due	2,621	4,637
Total Accruing Past Due	47,912	51,251
Non-accrual	168,370	197,757
Total loans	22,459,664	21,128,489
Deferred fees and costs, net	30,099	30,790	$ 28,900
Home Equity Lines [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	1,667,552	1,659,869
Accruing 30-89 Days Past Due	5,882	6,992
Accruing 90 Days or Greater Past Due	0	703
Total Accruing Past Due	5,882	7,695
Non-accrual	16,480	16,434
Total loans	1,689,914	1,683,998
Consumer Mortgages [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	1,907,644	1,648,145
Accruing 30-89 Days Past Due	8,657	12,626
Accruing 90 Days or Greater Past Due	134	12
Total Accruing Past Due	8,791	12,638
Non-accrual	22,248	33,278
Total loans	1,938,683	1,694,061
Credit Cards [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	237,742	250,304
Accruing 30-89 Days Past Due	1,663	1,971
Accruing 90 Days or Greater Past Due	1,446	1,374
Total Accruing Past Due	3,109	3,345
Non-accrual	0	0
Total loans	240,851	253,649
Other Retail Loans [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	418,337	297,703
Accruing 30-89 Days Past Due	2,390	2,361
Accruing 90 Days or Greater Past Due	26	101
Total Accruing Past Due	2,416	2,462
Non-accrual	2,565	2,295
Total loans	423,318	302,460
Investment Properties [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	5,726,307	5,184,103
Accruing 30-89 Days Past Due	2,284	1,851
Accruing 90 Days or Greater Past Due	0	0
Total Accruing Past Due	2,284	1,851
Non-accrual	23,040	20,720
Total loans	5,751,631	5,206,674
1-4 Family Properties [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	1,086,612	1,105,186
Accruing 30-89 Days Past Due	6,300	4,067
Accruing 90 Days or Greater Past Due	103	432
Total Accruing Past Due	6,403	4,499
Non-accrual	16,839	24,197
Total loans	1,109,854	1,133,882
Land Acquisition [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	495,542	551,308
Accruing 30-89 Days Past Due	639	363
Accruing 90 Days or Greater Past Due	32	0
Total Accruing Past Due	671	363
Non-accrual	17,768	34,375
Total loans	513,981	586,046
Commercial Real Estate [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	7,308,461	6,840,597
Accruing 30-89 Days Past Due	9,223	6,281
Accruing 90 Days or Greater Past Due	135	432
Total Accruing Past Due	9,358	6,713
Non-accrual	57,647	79,292
Total loans	7,375,466	6,926,602
Commercial, Financial and Agricultural [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	6,410,338	6,130,184
Accruing 30-89 Days Past Due	12,222	9,979
Accruing 90 Days or Greater Past Due	785	1,790
Total Accruing Past Due	13,007	11,769
Non-accrual	49,137	40,359
Total loans	6,472,482	6,182,312
Owner-Occupied [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	4,293,308	4,052,679
Accruing 30-89 Days Past Due	5,254	6,404
Accruing 90 Days or Greater Past Due	95	225
Total Accruing Past Due	5,349	6,629
Non-accrual	20,293	26,099
Total loans	4,318,950	4,085,407
Commercial And Industrial [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	10,703,646	10,182,863
Accruing 30-89 Days Past Due	17,476	16,383
Accruing 90 Days or Greater Past Due	880	2,015
Total Accruing Past Due	18,356	18,398
Non-accrual	69,430	66,458
Total loans	10,791,432	10,267,719
Retail [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	4,231,275	3,856,021
Accruing 30-89 Days Past Due	18,592	23,950
Accruing 90 Days or Greater Past Due	1,606	2,190
Total Accruing Past Due	20,198	26,140
Non-accrual	41,293	52,007
Total loans	$ 4,292,766	$ 3,934,168