Loans and Allowance for Loan Losses (Troubled Debt Restructurings) (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2021 USD ($) Contract	Jun. 30, 2020 USD ($) Contract	Jun. 30, 2021 USD ($) Contract	Jun. 30, 2020 USD ($) Contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | Contract	56	96	198	200
Recorded investment	$ 6,801,000	$ 15,652,000	$ 22,274,000	$ 52,348,000
Net charge-offs	$ 0	$ 0	$ 0	$ 0
Total commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | Contract	23	47	68	88
Recorded investment	$ 4,099,000	$ 5,390,000	$ 11,547,000	$ 12,588,000
Total commercial and industrial | Commercial, financial and agricultural
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | Contract	18	40	58	76
Recorded investment	$ 2,944,000	$ 3,503,000	$ 8,739,000	$ 9,237,000
Total commercial and industrial | Owner-occupied
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | Contract	5	7	10	12
Recorded investment	$ 1,155,000	$ 1,887,000	$ 2,808,000	$ 3,351,000
Total commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | Contract	4	7	15	16
Recorded investment	$ 943,000	$ 6,308,000	$ 3,471,000	$ 30,994,000
Total commercial real estate | Investment properties
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | Contract	1	2	6	4
Recorded investment	$ 419,000	$ 5,599,000	$ 2,402,000	$ 28,669,000
Total commercial real estate | 1-4 family properties
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | Contract	2	4	7	10
Recorded investment	$ 158,000	$ 618,000	$ 660,000	$ 1,784,000
Total commercial real estate | Land and development
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | Contract	1	1	2	2
Recorded investment	$ 366,000	$ 91,000	$ 409,000	$ 541,000
Total consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | Contract	29	42	115	96
Recorded investment	$ 1,759,000	$ 3,954,000	$ 7,256,000	$ 8,766,000
Total consumer | Consumer mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | Contract	2	10	2	16
Recorded investment	$ 331,000	$ 2,038,000	$ 331,000	$ 3,638,000
Total consumer | Home equity lines
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | Contract	14	14	27	33
Recorded investment	$ 996,000	$ 1,099,000	$ 1,745,000	$ 2,337,000
Total consumer | Other consumer loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | Contract	13	18	86	47
Recorded investment	$ 432,000	$ 817,000	$ 5,180,000	$ 2,791,000
Below Market Interest Rate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	5,286,000	8,471,000	12,934,000	38,674,000
Below Market Interest Rate | Total commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	2,925,000	1,956,000	7,411,000	7,047,000
Below Market Interest Rate | Total commercial and industrial | Commercial, financial and agricultural
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	1,770,000	1,503,000	5,002,000	5,226,000
Below Market Interest Rate | Total commercial and industrial | Owner-occupied
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	1,155,000	453,000	2,409,000	1,821,000
Below Market Interest Rate | Total commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	943,000	5,759,000	3,389,000	30,003,000
Below Market Interest Rate | Total commercial real estate | Investment properties
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	419,000	5,599,000	2,402,000	28,669,000
Below Market Interest Rate | Total commercial real estate | 1-4 family properties
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	158,000	69,000	621,000	793,000
Below Market Interest Rate | Total commercial real estate | Land and development
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	366,000	91,000	366,000	541,000
Below Market Interest Rate | Total consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	1,418,000	756,000	2,134,000	1,624,000
Below Market Interest Rate | Total consumer | Consumer mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	331,000	556,000	331,000	1,072,000
Below Market Interest Rate | Total consumer | Home equity lines
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	900,000	181,000	1,487,000	455,000
Below Market Interest Rate | Total consumer | Other consumer loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	187,000	19,000	316,000	97,000
Other Concessions
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	1,515,000	7,181,000	9,340,000	13,674,000
Other Concessions | Total commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	1,174,000	3,434,000	4,136,000	5,541,000
Other Concessions | Total commercial and industrial | Commercial, financial and agricultural
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	1,174,000	2,000,000	3,737,000	4,011,000
Other Concessions | Total commercial and industrial | Owner-occupied
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	0	1,434,000	399,000	1,530,000
Other Concessions | Total commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	0	549,000	82,000	991,000
Other Concessions | Total commercial real estate | Investment properties
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	0	0	0	0
Other Concessions | Total commercial real estate | 1-4 family properties
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	0	549,000	39,000	991,000
Other Concessions | Total commercial real estate | Land and development
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	0	0	43,000	0
Other Concessions | Total consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	341,000	3,198,000	5,122,000	7,142,000
Other Concessions | Total consumer | Consumer mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	0	1,482,000	0	2,566,000
Other Concessions | Total consumer | Home equity lines
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	96,000	918,000	258,000	1,882,000
Other Concessions | Total consumer | Other consumer loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	245,000	798,000	4,864,000	2,694,000
Principal Forgiveness
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment	$ 0	$ 0	$ 0	$ 0