Loans And Allowance For Loan Losses (Troubled Debt Restructurings) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) Contract	Dec. 31, 2015 USD ($) Contract	Dec. 31, 2014 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	169	262	272
Post-modification balance for loans modified or renewed	$ 52,994	$ 80,386	$ 114,298
Write-down	$ 0	$ 4,000	$ 163
Home Equity Lines [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	5	53	20
Post-modification balance for loans modified or renewed	$ 348	$ 5,731	$ 2,786
Consumer Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	7	15	19
Post-modification balance for loans modified or renewed	$ 464	$ 1,906	$ 3,602
Credit Card Receivable [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	0	0	0
Post-modification balance for loans modified or renewed	$ 0	$ 0	$ 0
Other Retail Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	28	27	27
Post-modification balance for loans modified or renewed	$ 2,650	$ 1,147	$ 1,229
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	57	66	99
Post-modification balance for loans modified or renewed	$ 16,429	$ 56,424	$ 37,148
Investment Properties [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	4	11	15
Post-modification balance for loans modified or renewed	$ 5,343	$ 32,025	$ 14,236
1-4 Family Properties [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	39	43	68
Post-modification balance for loans modified or renewed	$ 6,987	$ 22,253	$ 13,103
Land Acquisition [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	14	12	16
Post-modification balance for loans modified or renewed	$ 4,099	$ 2,146	$ 9,809
Commercial And Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	72	101	107
Post-modification balance for loans modified or renewed	$ 33,103	$ 15,178	$ 69,533
Commercial, Financial and Agricultural [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	63	91	89
Post-modification balance for loans modified or renewed	$ 24,669	$ 9,697	$ 31,267
Owner-Occupied [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	9	10	18
Post-modification balance for loans modified or renewed	$ 8,434	$ 5,481	$ 38,266
Retail [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	40	95	66
Post-modification balance for loans modified or renewed	$ 3,462	$ 8,784	$ 7,617
Principal Forgiveness [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	0	14,852	2,398
Principal Forgiveness [Member] | Home Equity Lines [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	0	0	0
Principal Forgiveness [Member] | Consumer Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	0	0	0
Principal Forgiveness [Member] | Credit Card Receivable [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	0	0	0
Principal Forgiveness [Member] | Other Retail Loans [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	0	0	0
Principal Forgiveness [Member] | Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	0	14,823	2,338
Principal Forgiveness [Member] | Investment Properties [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	0	0	0
Principal Forgiveness [Member] | 1-4 Family Properties [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	0	14,823	0
Principal Forgiveness [Member] | Land Acquisition [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	0	0	2,338
Principal Forgiveness [Member] | Commercial And Industrial [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	0	29	60
Principal Forgiveness [Member] | Commercial, Financial and Agricultural [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	0	29	60
Principal Forgiveness [Member] | Owner-Occupied [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	0	0	0
Principal Forgiveness [Member] | Retail [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	0	0	0
Below Market Interest Rate [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	33,749	41,222	59,020
Below Market Interest Rate [Member] | Home Equity Lines [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	225	2,826	2,335
Below Market Interest Rate [Member] | Consumer Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	413	1,011	2,735
Below Market Interest Rate [Member] | Credit Card Receivable [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	0	0	0
Below Market Interest Rate [Member] | Other Retail Loans [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	394	444	663
Below Market Interest Rate [Member] | Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	7,324	30,333	19,817
Below Market Interest Rate [Member] | Investment Properties [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	1,825	25,052	8,423
Below Market Interest Rate [Member] | 1-4 Family Properties [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	5,499	4,667	6,611
Below Market Interest Rate [Member] | Land Acquisition [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	0	614	4,783
Below Market Interest Rate [Member] | Commercial And Industrial [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	25,393	6,608	33,470
Below Market Interest Rate [Member] | Commercial, Financial and Agricultural [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	17,509	3,191	10,066
Below Market Interest Rate [Member] | Owner-Occupied [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	7,884	3,417	23,404
Below Market Interest Rate [Member] | Retail [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	1,032	4,281	5,733
Term Extensions and/or Other Concessions [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	19,245	24,312	52,880
Term Extensions and/or Other Concessions [Member] | Home Equity Lines [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	123	2,905	451
Term Extensions and/or Other Concessions [Member] | Consumer Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	51	895	867
Term Extensions and/or Other Concessions [Member] | Credit Card Receivable [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	0	0	0
Term Extensions and/or Other Concessions [Member] | Other Retail Loans [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	2,256	703	566
Term Extensions and/or Other Concessions [Member] | Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	9,105	11,268	14,993
Term Extensions and/or Other Concessions [Member] | Investment Properties [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	3,518	6,973	5,813
Term Extensions and/or Other Concessions [Member] | 1-4 Family Properties [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	1,488	2,763	6,492
Term Extensions and/or Other Concessions [Member] | Land Acquisition [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	4,099	1,532	2,688
Term Extensions and/or Other Concessions [Member] | Commercial And Industrial [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	7,710	8,541	36,003
Term Extensions and/or Other Concessions [Member] | Commercial, Financial and Agricultural [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	7,160	6,477	21,141
Term Extensions and/or Other Concessions [Member] | Owner-Occupied [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	550	2,064	14,862
Term Extensions and/or Other Concessions [Member] | Retail [Member]
Financing Receivable, Modifications [Line Items]
Post-modification balance for loans modified or renewed	$ 2,430	$ 4,503	$ 1,884