Loans And Allowance For Loan Losses (Schedule Of Impaired Loans) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	$ 35,108	$ 65,256
Unpaid Principal Balance, With no related allowance recorded	78,312	125,470
Related Allowance, With no related allowance recorded	0	0
Average Recorded Investment, With no related allowance recorded	50,030	90,590
Interest Income Recognized, With no related allowance recorded	0	0
Recorded Investment, With allowance recorded	266,692	376,892
Unpaid Principal Balance, With allowance recorded	270,004	380,036
Related Allowance, With allowance recorded	30,435	33,476
Average Recorded Investment, With allowance recorded	308,224	531,456
Interest Income Recognized, With allowance recorded	9,522	14,861
Recorded Investment	301,800	442,148
Unpaid Principal Balance	348,316	505,506
Related Allowance	30,435	33,476
Average Recorded Investment in Impaired Loans	358,254	622,046	$ 952,300
Interest Income Recognized	9,522	14,861
Home Equity Lines [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	1,030	0
Unpaid Principal Balance, With no related allowance recorded	1,030	0
Related Allowance, With no related allowance recorded	0	0
Average Recorded Investment, With no related allowance recorded	573	0
Interest Income Recognized, With no related allowance recorded	0	0
Recorded Investment, With allowance recorded	9,575	4,848
Unpaid Principal Balance, With allowance recorded	9,575	4,848
Related Allowance, With allowance recorded	206	129
Average Recorded Investment, With allowance recorded	8,318	3,604
Interest Income Recognized, With allowance recorded	346	1,405
Recorded Investment	10,605	4,848
Unpaid Principal Balance	10,605	4,848
Related Allowance	206	129
Average Recorded Investment in Impaired Loans	8,891	3,604
Interest Income Recognized	346	1,405
Consumer Mortgages [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	814	995
Unpaid Principal Balance, With no related allowance recorded	941	2,065
Related Allowance, With no related allowance recorded	0	0
Average Recorded Investment, With no related allowance recorded	995	1,352
Interest Income Recognized, With no related allowance recorded	0	0
Recorded Investment, With allowance recorded	22,173	33,450
Unpaid Principal Balance, With allowance recorded	23,297	33,450
Related Allowance, With allowance recorded	651	1,040
Average Recorded Investment, With allowance recorded	26,044	39,427
Interest Income Recognized, With allowance recorded	1,229	115
Recorded Investment	22,987	34,445
Unpaid Principal Balance	24,238	35,515
Related Allowance	651	1,040
Average Recorded Investment in Impaired Loans	27,039	40,779
Interest Income Recognized	1,229	115
Credit Cards [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	0	0
Unpaid Principal Balance, With no related allowance recorded	0	0
Related Allowance, With no related allowance recorded	0	0
Average Recorded Investment, With no related allowance recorded	0	0
Interest Income Recognized, With no related allowance recorded	0	0
Recorded Investment, With allowance recorded	0	0
Unpaid Principal Balance, With allowance recorded	0	0
Related Allowance, With allowance recorded	0	0
Average Recorded Investment, With allowance recorded	0	0
Interest Income Recognized, With allowance recorded	0	0
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Related Allowance	0	0
Average Recorded Investment in Impaired Loans	0	0
Interest Income Recognized	0	0
Other Retail Loans [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	0	0
Unpaid Principal Balance, With no related allowance recorded	0	0
Related Allowance, With no related allowance recorded	0	0
Average Recorded Investment, With no related allowance recorded	0	0
Interest Income Recognized, With no related allowance recorded	0	0
Recorded Investment, With allowance recorded	4,651	5,293
Unpaid Principal Balance, With allowance recorded	4,651	5,293
Related Allowance, With allowance recorded	132	101
Average Recorded Investment, With allowance recorded	5,105	4,997
Interest Income Recognized, With allowance recorded	323	315
Recorded Investment	4,651	5,293
Unpaid Principal Balance	4,651	5,293
Related Allowance	132	101
Average Recorded Investment in Impaired Loans	5,105	4,997
Interest Income Recognized	323	315
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	20,109	39,853
Unpaid Principal Balance, With no related allowance recorded	57,525	92,600
Related Allowance, With no related allowance recorded	0	0
Average Recorded Investment, With no related allowance recorded	28,068	60,706
Interest Income Recognized, With no related allowance recorded	0	0
Recorded Investment, With allowance recorded	137,849	211,683
Unpaid Principal Balance, With allowance recorded	138,419	214,803
Related Allowance, With allowance recorded	18,969	21,755
Average Recorded Investment, With allowance recorded	169,694	313,257
Interest Income Recognized, With allowance recorded	4,685	8,024
Recorded Investment	157,958	251,536
Unpaid Principal Balance	195,944	307,403
Related Allowance	18,969	21,755
Average Recorded Investment in Impaired Loans	197,762	373,963
Interest Income Recognized	4,685	8,024
Investment Properties [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	10,051	15,368
Unpaid Principal Balance, With no related allowance recorded	12,946	20,237
Related Allowance, With no related allowance recorded	0	0
Average Recorded Investment, With no related allowance recorded	11,625	25,311
Interest Income Recognized, With no related allowance recorded	0	0
Recorded Investment, With allowance recorded	62,305	81,758
Unpaid Principal Balance, With allowance recorded	62,305	83,963
Related Allowance, With allowance recorded	10,070	5,413
Average Recorded Investment, With allowance recorded	73,211	129,289
Interest Income Recognized, With allowance recorded	2,131	3,690
Recorded Investment	72,356	97,126
Unpaid Principal Balance	75,251	104,200
Related Allowance	10,070	5,413
Average Recorded Investment in Impaired Loans	84,836	154,600
Interest Income Recognized	2,131	3,690
1-4 Family Properties [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	1,507	2,981
Unpaid Principal Balance, With no related allowance recorded	5,526	10,520
Related Allowance, With no related allowance recorded	0	0
Average Recorded Investment, With no related allowance recorded	2,546	5,441
Interest Income Recognized, With no related allowance recorded	0	0
Recorded Investment, With allowance recorded	51,376	80,625
Unpaid Principal Balance, With allowance recorded	51,376	81,357
Related Allowance, With allowance recorded	6,184	11,442
Average Recorded Investment, With allowance recorded	61,690	94,773
Interest Income Recognized, With allowance recorded	1,618	2,645
Recorded Investment	52,883	83,606
Unpaid Principal Balance	56,902	91,877
Related Allowance	6,184	11,442
Average Recorded Investment in Impaired Loans	64,236	100,214
Interest Income Recognized	1,618	2,645
Land Acquisition [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	8,551	21,504
Unpaid Principal Balance, With no related allowance recorded	39,053	61,843
Related Allowance, With no related allowance recorded	0	0
Average Recorded Investment, With no related allowance recorded	13,897	29,954
Interest Income Recognized, With no related allowance recorded	0	0
Recorded Investment, With allowance recorded	24,168	49,300
Unpaid Principal Balance, With allowance recorded	24,738	49,483
Related Allowance, With allowance recorded	2,715	4,900
Average Recorded Investment, With allowance recorded	34,793	89,195
Interest Income Recognized, With allowance recorded	936	1,689
Recorded Investment	32,719	70,804
Unpaid Principal Balance	63,791	111,326
Related Allowance	2,715	4,900
Average Recorded Investment in Impaired Loans	48,690	119,149
Interest Income Recognized	936	1,689
Commercial And Industrial [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	13,155	24,408
Unpaid Principal Balance, With no related allowance recorded	18,816	30,805
Related Allowance, With no related allowance recorded	0	0
Average Recorded Investment, With no related allowance recorded	20,394	28,532
Interest Income Recognized, With no related allowance recorded	0	0
Recorded Investment, With allowance recorded	92,444	121,618
Unpaid Principal Balance, With allowance recorded	94,062	121,642
Related Allowance, With allowance recorded	10,477	10,451
Average Recorded Investment, With allowance recorded	99,063	170,171
Interest Income Recognized, With allowance recorded	2,939	5,002
Recorded Investment	105,599	146,026
Unpaid Principal Balance	112,878	152,447
Related Allowance	10,477	10,451
Average Recorded Investment in Impaired Loans	119,457	198,703
Interest Income Recognized	2,939	5,002
Commercial, Financial and Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	4,393	7,391
Unpaid Principal Balance, With no related allowance recorded	7,606	11,193
Related Allowance, With no related allowance recorded	0	0
Average Recorded Investment, With no related allowance recorded	5,737	8,984
Interest Income Recognized, With no related allowance recorded	0	0
Recorded Investment, With allowance recorded	42,914	59,035
Unpaid Principal Balance, With allowance recorded	44,374	59,041
Related Allowance, With allowance recorded	8,339	7,597
Average Recorded Investment, With allowance recorded	43,740	91,221
Interest Income Recognized, With allowance recorded	1,125	2,392
Recorded Investment	47,307	66,426
Unpaid Principal Balance	51,980	70,234
Related Allowance	8,339	7,597
Average Recorded Investment in Impaired Loans	49,477	100,205
Interest Income Recognized	1,125	2,392
Owner-Occupied [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	8,762	17,017
Unpaid Principal Balance, With no related allowance recorded	11,210	19,612
Related Allowance, With no related allowance recorded	0	0
Average Recorded Investment, With no related allowance recorded	14,657	19,548
Interest Income Recognized, With no related allowance recorded	0	0
Recorded Investment, With allowance recorded	49,530	62,583
Unpaid Principal Balance, With allowance recorded	49,688	62,601
Related Allowance, With allowance recorded	2,138	2,854
Average Recorded Investment, With allowance recorded	55,323	78,950
Interest Income Recognized, With allowance recorded	1,814	2,610
Recorded Investment	58,292	79,600
Unpaid Principal Balance	60,898	82,213
Related Allowance	2,138	2,854
Average Recorded Investment in Impaired Loans	69,980	98,498
Interest Income Recognized	1,814	2,610
Retail [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	1,844	995
Unpaid Principal Balance, With no related allowance recorded	1,971	2,065
Related Allowance, With no related allowance recorded	0	0
Average Recorded Investment, With no related allowance recorded	1,568	1,352
Interest Income Recognized, With no related allowance recorded	0	0
Recorded Investment, With allowance recorded	36,399	43,591
Unpaid Principal Balance, With allowance recorded	37,523	43,591
Related Allowance, With allowance recorded	989	1,270
Average Recorded Investment, With allowance recorded	39,467	48,028
Interest Income Recognized, With allowance recorded	1,898	1,835
Recorded Investment	38,243	44,586
Unpaid Principal Balance	39,494	45,656
Related Allowance	989	1,270
Average Recorded Investment in Impaired Loans	41,035	49,380
Interest Income Recognized	$ 1,898	$ 1,835