Allowance For Credit Losses (Activity In The Allowance For Loan Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 86,886	$ 61,503	$ 85,675	$ 56,679
Financing Receivable, Allowance for Credit Loss, Writeoff	1,070	2,130	2,771	4,815
Financing Receivable, Allowance for Credit Loss, Recovery	1,801	1,879	3,478	4,235
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Total	(731)	251	(707)	580
Provision for Loan, Lease, and Other Losses	(4,040)	12,224	(8,895)	17,377
Ending balance	83,577	73,476	83,577	73,476
Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			6,090
Commercial Financial And Agricultural [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	16,279	21,544	25,608	20,203
Financing Receivable, Allowance for Credit Loss, Writeoff	308	277	454	800
Financing Receivable, Allowance for Credit Loss, Recovery	232	180	355	880
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Total	76	97	99	(80)
Provision for Loan, Lease, and Other Losses	(981)	2,029	(2,030)	3,193
Ending balance	15,222	23,476	15,222	23,476
Commercial Financial And Agricultural [Member] \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			(8,257)
Commercial Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	24,487	11,591	23,480	10,229
Financing Receivable, Allowance for Credit Loss, Writeoff	0	0	0	0
Financing Receivable, Allowance for Credit Loss, Recovery	210	343	296	643
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Total	(210)	(343)	(296)	(643)
Provision for Loan, Lease, and Other Losses	(1,948)	4,535	(3,146)	5,597
Ending balance	22,749	16,469	22,749	16,469
Commercial Real Estate [Member] \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			2,119
Construction Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	5,813	5,493	7,288	5,311
Financing Receivable, Allowance for Credit Loss, Writeoff	0	0	0	6
Financing Receivable, Allowance for Credit Loss, Recovery	229	363	481	593
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Total	(229)	(363)	(481)	(587)
Provision for Loan, Lease, and Other Losses	(372)	972	(201)	930
Ending balance	5,670	6,828	5,670	6,828
Construction Real Estate [Member] \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			(1,898)
Residential Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	14,037	9,017	11,363	8,610
Financing Receivable, Allowance for Credit Loss, Writeoff	26	71	37	142
Financing Receivable, Allowance for Credit Loss, Recovery	68	172	130	268
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Total	(42)	(101)	(93)	(126)
Provision for Loan, Lease, and Other Losses	(966)	1,389	(1,464)	1,771
Ending balance	13,113	10,507	13,113	10,507
Residential Real Estate [Member] \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			3,121
Consumer [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	25,729	13,728	17,418	12,211
Financing Receivable, Allowance for Credit Loss, Writeoff	736	1,767	2,280	3,852
Financing Receivable, Allowance for Credit Loss, Recovery	1,062	821	2,216	1,851
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Total	(326)	946	64	2,001
Provision for Loan, Lease, and Other Losses	206	2,842	(2,018)	5,414
Ending balance	26,261	15,624	26,261	15,624
Consumer [Member] \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			10,925
Finance Leases Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	541	130	518	115
Financing Receivable, Allowance for Credit Loss, Writeoff	0	15	0	15
Financing Receivable, Allowance for Credit Loss, Recovery	0	0	0	0
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Total	0	15	0	15
Provision for Loan, Lease, and Other Losses	21	457	(36)	472
Ending balance	$ 562	$ 572	562	$ 572
Finance Leases Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			$ 80

Amount, after recovery, of writeoff of financing receivable, charged against allowance for credit loss.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (4)

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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