Allowance for Credit Losses (Impairment By Loan Class) (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Individually Evaluated for Impairment, Recorded Investment	$ 1,341	$ 1,667
Loans Individually Evaluated for Impairment, Allowance	70	99
Loans Collectively Evaluated for Impairment, Recorded Investment	7,025,788	7,207,484
Loans Collectively Evaluated for Impairment, Allowance	112,502	110,275
Commercial, financial and agricultural \| Domestic \| Commercial.
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Individually Evaluated for Impairment, Recorded Investment	238	298
Loans Individually Evaluated for Impairment, Allowance		29
Loans Collectively Evaluated for Impairment, Recorded Investment	1,475,126	1,501,554
Loans Collectively Evaluated for Impairment, Allowance	25,577	23,149
Commercial, financial and agricultural \| Domestic \| Commercial real estate: farmland & commercial
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Individually Evaluated for Impairment, Recorded Investment	333	562
Loans Collectively Evaluated for Impairment, Recorded Investment	2,542,421	2,710,494
Loans Collectively Evaluated for Impairment, Allowance	35,270	35,654
Commercial, financial and agricultural \| Domestic \| Commercial real estate: multifamily
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Individually Evaluated for Impairment, Recorded Investment	123	131
Loans Collectively Evaluated for Impairment, Recorded Investment	233,822	284,405
Loans Collectively Evaluated for Impairment, Allowance	2,856	3,291
Obligations of states and political subdivisions \| Domestic \| Commercial Real Estate: other construction and land development
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Individually Evaluated for Impairment, Recorded Investment	564	589
Loans Individually Evaluated for Impairment, Allowance	70	70
Loans Collectively Evaluated for Impairment, Recorded Investment	1,732,670	1,667,524
Loans Collectively Evaluated for Impairment, Allowance	36,643	35,320
Real estate - mortgage \| Domestic \| Residential: first lien
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Individually Evaluated for Impairment, Recorded Investment	83	87
Loans Collectively Evaluated for Impairment, Recorded Investment	405,303	403,571
Loans Collectively Evaluated for Impairment, Allowance	4,137	4,073
Real estate - mortgage \| Domestic \| Residential Junior Lien
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Collectively Evaluated for Impairment, Recorded Investment	437,356	464,173
Loans Collectively Evaluated for Impairment, Allowance	6,894	7,754
Consumer \| Domestic
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Collectively Evaluated for Impairment, Recorded Investment	40,815	40,966
Loans Collectively Evaluated for Impairment, Allowance	270	272
Foreign. \| Foreign
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Collectively Evaluated for Impairment, Recorded Investment	158,275	134,797
Loans Collectively Evaluated for Impairment, Allowance	$ 855	$ 762

- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

No definition available.

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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