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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	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	$ 17,375	$ 22,575
Accruing Current	4,304,404	4,203,565
Loans	4,337,713	4,247,765	$ 4,149,459
Unamortized net deferred loan costs (fees)	1,784	1,299	(69)
Total loans	4,339,497	4,249,064	4,149,390
Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	11,220	18,324
Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	4,092	2,718
Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	622	583
PCI Loans
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	0	0
Accruing Current	13,212	15,682
Loans	14,175	17,393
PCI Loans \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	167	990
PCI Loans \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	174	138
PCI Loans \| Accruing 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	622	583
Commercial, financial, and agricultural
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	1,490	919
Accruing Current	465,112	455,691
Loans	471,188	457,037	417,366
Commercial, financial, and agricultural \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	3,716	191
Commercial, financial, and agricultural \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	606	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	4,260	7,452
Accruing Current	1,884,964	1,768,205
Loans	1,900,188	1,787,022	1,690,175
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	1,007	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	2,514	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	1,420	2,265
Accruing Current	454,890	515,472
Loans	456,781	518,976	600,031
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	299	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	1,404	1,685
Accruing Current	346,265	355,831
Loans	349,355	359,162	369,875
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	856	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	620	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	8,697	10,115
Accruing Current	1,071,040	1,022,262
Loans	1,090,601	1,054,176	1,000,189
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	4,821	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	101	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	68,921	70,422
Loans	69,600	71,392	$ 71,823
Installment loans to individuals \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	354	359
Installment loans to individuals \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable, past due	77	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	470,924	456,806
Loans, Excluding Purchased Credit Impaired Loans \| Real estate, commercial \| Real estate – mortgage – commercial and other
Financing Receivable, Past Due [Line Items]
Loans	1,892,745	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	456,609	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	349,145	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	1,084,659	1,047,924
Loans, Excluding Purchased Credit Impaired Loans \| Installment loans to individuals
Financing Receivable, Past Due [Line Items]
Loans	$ 69,456	$ 71,140