Allowance For Loan Losses (Activity In The Allowance For Loan Losses) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 54,352	$ 59,468
Charge-offs	3,418	3,827
Recoveries	2,842	6,841
Net Charge-offs	576	(3,014)
Provision	1,632	(2,225)
Ending balance	55,408	60,257
Commercial Financial And Agricultural [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	10,719	14,218
Charge-offs	352	639
Recoveries	291	247
Net Charge-offs	61	392
Provision	703	(64)
Ending balance	11,361	13,762
Commercial Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	8,808	15,899
Charge-offs	130	794
Recoveries	674	1,558
Net Charge-offs	(544)	(764)
Provision	(56)	(909)
Ending balance	9,296	15,754
Construction Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	8,652	6,855
Charge-offs	0	8
Recoveries	285	794
Net Charge-offs	(285)	(786)
Provision	(182)	480
Ending balance	8,755	8,121
Residential Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	14,772	14,251
Charge-offs	422	591
Recoveries	924	1,227
Net Charge-offs	(502)	(636)
Provision	(762)	(680)
Ending balance	14,512	14,207
Consumer [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	11,401	8,245
Charge-offs	2,514	1,795
Recoveries	666	3,014
Net Charge-offs	1,848	(1,219)
Provision	1,931	(1,051)
Ending balance	11,484	8,413
Leases [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	0	0
Charge-offs	0	0
Recoveries	2	1
Net Charge-offs	(2)	(1)
Provision	(2)	(1)
Ending balance	$ 0	$ 0

Financing Receivables Allowance For Credit Losses Net Charge Offs

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

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Amount of direct write-downs of financing receivables charged against the allowance.

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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