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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	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	$ 19,720	$ 22,575
Accruing Current	4,358,380	4,203,565
Loans	4,394,984	4,247,765	$ 4,190,139
Unamortized net deferred loan costs	1,560	1,299	489
Total loans	4,396,544	4,249,064	4,190,628
Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	13,583	18,324
Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	2,236	2,718
Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	1,065	583
PCI Loans
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	0	0
Accruing Current	12,337	15,682
Loans	13,798	17,393
PCI Loans \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	6	990
PCI Loans \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	390	138
PCI Loans \| Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	1,065	583
Commercial, financial, and agricultural
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	2,472	919
Accruing Current	477,964	455,691
Loans	486,768	457,037	435,730
Commercial, financial, and agricultural \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	5,995	191
Commercial, financial, and agricultural \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	95	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	6,370	7,452
Accruing Current	1,911,677	1,768,205
Loans	1,928,931	1,787,022	1,723,598
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	3,376	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	121	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	1,235	2,265
Accruing Current	469,119	515,472
Loans	471,326	518,976	559,450
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	803	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	0	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	1,878	1,685
Accruing Current	340,180	355,831
Loans	343,378	359,162	362,829
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	712	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	399	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	7,661	10,115
Accruing Current	1,076,708	1,022,262
Loans	1,093,619	1,054,176	1,038,436
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	2,392	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	1,185	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	104	139
Accruing Current	70,395	70,422
Loans	70,962	71,392	$ 70,096
Installment loans to individuals \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	299	359
Installment loans to individuals \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	46	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	486,526	456,806
Loans, Excluding Purchased Credit Impaired Loans \| Real estate, commercial \| Real estate – mortgage – commercial and other
Financing Receivable, Past Due [Line Items]
Loans	1,921,544	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	471,157	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	343,169	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	1,087,946	1,047,924
Loans, Excluding Purchased Credit Impaired Loans \| Installment loans to individuals
Financing Receivable, Past Due [Line Items]
Loans	$ 70,844	$ 71,140