Allowance for Credit Losses (Impairment By Loan Class) (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Individually Evaluated for Impairment, Recorded Investment	$ 1,409	$ 1,667
Loans Individually Evaluated for Impairment, Allowance	70	99
Loans Collectively Evaluated for Impairment, Recorded Investment	7,049,341	7,207,484
Loans Collectively Evaluated for Impairment, Allowance	119,125	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	108	298
Loans Individually Evaluated for Impairment, Allowance		29
Loans Collectively Evaluated for Impairment, Recorded Investment	1,448,415	1,501,554
Loans Collectively Evaluated for Impairment, Allowance	24,844	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	537	562
Loans Collectively Evaluated for Impairment, Recorded Investment	2,461,342	2,710,494
Loans Collectively Evaluated for Impairment, Allowance	34,974	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	121	131
Loans Collectively Evaluated for Impairment, Recorded Investment	245,685	284,405
Loans Collectively Evaluated for Impairment, Allowance	3,093	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	562	589
Loans Individually Evaluated for Impairment, Allowance	70	70
Loans Collectively Evaluated for Impairment, Recorded Investment	1,835,485	1,667,524
Loans Collectively Evaluated for Impairment, Allowance	41,998	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	81	87
Loans Collectively Evaluated for Impairment, Recorded Investment	412,271	403,571
Loans Collectively Evaluated for Impairment, Allowance	4,687	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	439,812	464,173
Loans Collectively Evaluated for Impairment, Allowance	8,272	7,754
Consumer \| Domestic
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Collectively Evaluated for Impairment, Recorded Investment	41,786	40,966
Loans Collectively Evaluated for Impairment, Allowance	292	272
Foreign. \| Foreign
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans Collectively Evaluated for Impairment, Recorded Investment	164,545	134,797
Loans Collectively Evaluated for Impairment, Allowance	$ 965	$ 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.

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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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