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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Loans and Asset Quality Information (Schedule of Analysis of Payment Status of Loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	$ 24,866	$ 22,575
Accruing Current	4,402,978	4,203,565
Loans	4,451,525	4,247,765	$ 4,043,355
Unamortized net deferred loan costs	1,941	1,299	(986)
Total loans	4,453,466	4,249,064	4,042,369
Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	17,236	18,324
Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	5,683	2,718
Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	762	583
PCI Loans
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	0	0
Accruing Current	11,646	15,682
Loans	12,664	17,393
PCI Loans \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	218	990
PCI Loans \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	38	138
PCI Loans \| Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	762	583
Commercial, financial, and agricultural
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	5,518	919
Accruing Current	497,788	455,692
Loans	504,271	457,037	381,130
Commercial, financial, and agricultural \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	752	191
Commercial, financial, and agricultural \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	0	5
Commercial, financial, and agricultural \| Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	0	0
Real estate, commercial \| Real estate – mortgage – commercial and other
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	8,820	7,452
Accruing Current	1,897,573	1,768,205
Loans	1,917,280	1,787,022	1,696,107
Real estate, commercial \| Real estate – mortgage – commercial and other \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	4,257	709
Real estate, commercial \| Real estate – mortgage – commercial and other \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	0	520
Real estate, commercial \| Real estate – mortgage – commercial and other \| Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	0	0
Real estate, commercial \| Real estate – construction, land development & other land loans
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	1,067	2,265
Accruing Current	529,444	515,472
Loans	530,866	518,976	539,020
Real estate, commercial \| Real estate – construction, land development & other land loans \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	37	849
Real estate, commercial \| Real estate – construction, land development & other land loans \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	152	212
Real estate, commercial \| Real estate – construction, land development & other land loans \| Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	0	0
Real estate, mortgage \| Real estate – mortgage – home equity loans / lines of credit
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	1,797	1,685
Accruing Current	334,832	355,831
Loans	337,922	359,162	379,978
Real estate, mortgage \| Real estate – mortgage – home equity loans / lines of credit \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	770	1,048
Real estate, mortgage \| Real estate – mortgage – home equity loans / lines of credit \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	300	254
Real estate, mortgage \| Real estate – mortgage – home equity loans / lines of credit \| Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	0	0
Real estate, mortgage \| Real estate – mortgage – residential (1-4 family) first mortgages
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	7,552	10,115
Accruing Current	1,076,205	1,022,261
Loans	1,105,014	1,054,176	972,772
Real estate, mortgage \| Real estate – mortgage – residential (1-4 family) first mortgages \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	10,858	14,178
Real estate, mortgage \| Real estate – mortgage – residential (1-4 family) first mortgages \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	5,056	1,369
Real estate, mortgage \| Real estate – mortgage – residential (1-4 family) first mortgages \| Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	0	0
Installment loans to individuals
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	112	139
Accruing Current	55,490	70,422
Loans	56,172	71,392	$ 74,348
Installment loans to individuals \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	344	359
Installment loans to individuals \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	137	220
Installment loans to individuals \| Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	0	0
Loans, Excluding Purchased Credit Impaired Loans \| Commercial, financial, and agricultural
Financing Receivable, Past Due [Line Items]
Loans	504,058	456,807
Loans, Excluding Purchased Credit Impaired Loans \| Real estate, commercial \| Real estate – mortgage – commercial and other
Financing Receivable, Past Due [Line Items]
Loans	1,910,650	1,776,886
Loans, Excluding Purchased Credit Impaired Loans \| Real estate, commercial \| Real estate – construction, land development & other land loans
Financing Receivable, Past Due [Line Items]
Loans	530,700	518,798
Loans, Excluding Purchased Credit Impaired Loans \| Real estate, mortgage \| Real estate – mortgage – home equity loans / lines of credit
Financing Receivable, Past Due [Line Items]
Loans	337,699	358,818
Loans, Excluding Purchased Credit Impaired Loans \| Real estate, mortgage \| Real estate – mortgage – residential (1-4 family) first mortgages
Financing Receivable, Past Due [Line Items]
Loans	1,099,671	1,047,923
Loans, Excluding Purchased Credit Impaired Loans \| Installment loans to individuals
Financing Receivable, Past Due [Line Items]
Loans	$ 56,083	$ 71,140