Loans and Asset Quality Information (Schedule of Recorded Investment in Loans by Credit Quality Indicators) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	$ 4,819,175	$ 4,451,525	$ 4,394,984
Unamortized net deferred loan costs (fees)	(5,439)	1,941	1,560
Total loans	4,813,736	4,453,466	4,396,544
Commercial, financial, and agricultural
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	804,831	504,271	486,768
Consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	50,189	56,172	70,962
Loans, Excluding Purchased Credit Impaired Loans | Commercial, financial, and agricultural
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	804,655	504,058
Loans, Excluding Purchased Credit Impaired Loans | Consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	50,141	56,083
Real estate – construction, land development & other land loans | Real estate, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	653,120	530,866	471,326
Real estate – construction, land development & other land loans | Loans, Excluding Purchased Credit Impaired Loans | Real estate, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	652,970	530,700
Real estate – mortgage – residential (1-4 family) first mortgages | Real estate, mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,017,087	1,105,014	1,093,619
Real estate – mortgage – residential (1-4 family) first mortgages | Loans, Excluding Purchased Credit Impaired Loans | Real estate, mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,011,912	1,099,671
Real estate – mortgage – home equity loans / lines of credit | Real estate, mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	310,326	337,922	343,378
Real estate – mortgage – home equity loans / lines of credit | Loans, Excluding Purchased Credit Impaired Loans | Real estate, mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	310,230	337,699
Real estate – mortgage – commercial and other | Real estate, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,983,622	1,917,280	$ 1,928,931
Real estate – mortgage – commercial and other | Loans, Excluding Purchased Credit Impaired Loans | Real estate, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,979,651	1,910,650
PCI Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	9,616	12,664
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	4,695,275	4,338,381
Pass | Loans, Excluding Purchased Credit Impaired Loans | Commercial, financial, and agricultural
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	778,593	486,081
Pass | Loans, Excluding Purchased Credit Impaired Loans | Consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	49,658	55,203
Pass | Real estate – construction, land development & other land loans | Loans, Excluding Purchased Credit Impaired Loans | Real estate, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	643,826	522,767
Pass | Real estate – mortgage – residential (1-4 family) first mortgages | Loans, Excluding Purchased Credit Impaired Loans | Real estate, mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	985,925	1,063,735
Pass | Real estate – mortgage – home equity loans / lines of credit | Loans, Excluding Purchased Credit Impaired Loans | Real estate, mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	300,708	328,903
Pass | Real estate – mortgage – commercial and other | Loans, Excluding Purchased Credit Impaired Loans | Real estate, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,928,787	1,873,594
Pass | PCI Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	7,778	8,098
Special Mention Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	65,286	50,321
Special Mention Loans | Loans, Excluding Purchased Credit Impaired Loans | Commercial, financial, and agricultural
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	16,517	7,998
Special Mention Loans | Loans, Excluding Purchased Credit Impaired Loans | Consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	85	413
Special Mention Loans | Real estate – construction, land development & other land loans | Loans, Excluding Purchased Credit Impaired Loans | Real estate, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	7,058	4,075
Special Mention Loans | Real estate – mortgage – residential (1-4 family) first mortgages | Loans, Excluding Purchased Credit Impaired Loans | Real estate, mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	7,634	13,187
Special Mention Loans | Real estate – mortgage – home equity loans / lines of credit | Loans, Excluding Purchased Credit Impaired Loans | Real estate, mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,854	1,258
Special Mention Loans | Real estate – mortgage – commercial and other | Loans, Excluding Purchased Credit Impaired Loans | Real estate, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	32,052	20,800
Special Mention Loans | PCI Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	86	2,590
Classified Accruing Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	26,958	37,957
Classified Accruing Loans | Loans, Excluding Purchased Credit Impaired Loans | Commercial, financial, and agricultural
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,072	4,461
Classified Accruing Loans | Loans, Excluding Purchased Credit Impaired Loans | Consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	218	355
Classified Accruing Loans | Real estate – construction, land development & other land loans | Loans, Excluding Purchased Credit Impaired Loans | Real estate, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,214	2,791
Classified Accruing Loans | Real estate – mortgage – residential (1-4 family) first mortgages | Loans, Excluding Purchased Credit Impaired Loans | Real estate, mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	12,611	15,197
Classified Accruing Loans | Real estate – mortgage – home equity loans / lines of credit | Loans, Excluding Purchased Credit Impaired Loans | Real estate, mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	6,074	5,741
Classified Accruing Loans | Real estate – mortgage – commercial and other | Loans, Excluding Purchased Credit Impaired Loans | Real estate, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	4,017	7,436
Classified Accruing Loans | PCI Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,752	1,976
Classified Nonaccrual Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	31,656	24,866
Classified Nonaccrual Loans | Loans, Excluding Purchased Credit Impaired Loans | Commercial, financial, and agricultural
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	8,473	5,518
Classified Nonaccrual Loans | Loans, Excluding Purchased Credit Impaired Loans | Consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	180	112
Classified Nonaccrual Loans | Real estate – construction, land development & other land loans | Loans, Excluding Purchased Credit Impaired Loans | Real estate, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	872	1,067
Classified Nonaccrual Loans | Real estate – mortgage – residential (1-4 family) first mortgages | Loans, Excluding Purchased Credit Impaired Loans | Real estate, mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	5,742	7,552
Classified Nonaccrual Loans | Real estate – mortgage – home equity loans / lines of credit | Loans, Excluding Purchased Credit Impaired Loans | Real estate, mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,594	1,797
Classified Nonaccrual Loans | Real estate – mortgage – commercial and other | Loans, Excluding Purchased Credit Impaired Loans | Real estate, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	14,795	8,820
Classified Nonaccrual Loans | PCI Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	$ 0	$ 0