Loans and Leases - Credit Quality (Details) $ in Thousands	Sep. 30, 2020 USD ($)
Commercial Financial And Agricultural [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	$ 148,694
2019	103,907
2018	79,351
2017	44,910
2016	30,521
Prior	62,663
Revolving loans amortized cost basis	424,268
Total	894,314
Commercial Financial And Agricultural [Member] | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	147,403
2019	102,389
2018	78,294
2017	44,321
2016	29,672
Prior	60,750
Revolving loans amortized cost basis	410,169
Total	872,998
Commercial Financial And Agricultural [Member] | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2020	916
2019	804
2018	333
2017	529
2016	849
Prior	1,226
Revolving loans amortized cost basis	7,723
Total	12,380
Commercial Financial And Agricultural [Member] | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	375
2019	714
2018	724
2017	60
2016	0
Prior	687
Revolving loans amortized cost basis	6,376
Total	8,936
Paycheck Protection Program Loans
Financing Receivable, Credit Quality Indicator [Line Items]
2020	501,580
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving loans amortized cost basis	0
Total	501,580
Paycheck Protection Program Loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	501,580
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving loans amortized cost basis	0
Total	501,580
Paycheck Protection Program Loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving loans amortized cost basis	0
Total	0
Paycheck Protection Program Loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving loans amortized cost basis	0
Total	0
Real-Estate Commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	913,991
2019	508,912
2018	246,354
2017	292,248
2016	156,053
Prior	203,920
Revolving loans amortized cost basis	48,213
Total	2,369,691
Real-Estate Commercial [Member] | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	912,215
2019	494,465
2018	245,307
2017	279,472
2016	153,490
Prior	191,043
Revolving loans amortized cost basis	45,464
Total	2,321,456
Real-Estate Commercial [Member] | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2020	1,776
2019	13,082
2018	0
2017	1,128
2016	1,345
Prior	5,935
Revolving loans amortized cost basis	1,912
Total	25,178
Real-Estate Commercial [Member] | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	1,365
2018	1,047
2017	11,648
2016	1,218
Prior	6,942
Revolving loans amortized cost basis	837
Total	23,057
Real-Estate Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	106,614
2019	72,157
2018	45,140
2017	1,804
2016	2,950
Prior	0
Revolving loans amortized cost basis	4,925
Total	233,590
Real-Estate Construction [Member] | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	86,135
2019	72,157
2018	45,140
2017	1,804
2016	2,950
Prior	0
Revolving loans amortized cost basis	4,925
Total	213,111
Real-Estate Construction [Member] | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2020	20,479
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving loans amortized cost basis	0
Total	20,479
Real-Estate Construction [Member] | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving loans amortized cost basis	0
Total	0
Real Estate Residential Secured For Business Purpose [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	84,762
2019	77,314
2018	60,281
2017	47,390
2016	42,780
Prior	41,386
Revolving loans amortized cost basis	24,326
Total	378,239
Real Estate Residential Secured For Business Purpose [Member] | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	84,624
2019	76,313
2018	60,041
2017	47,244
2016	41,529
Prior	40,042
Revolving loans amortized cost basis	24,058
Total	373,851
Real Estate Residential Secured For Business Purpose [Member] | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2020	108
2019	464
2018	189
2017	77
2016	180
Prior	481
Revolving loans amortized cost basis	200
Total	1,699
Real Estate Residential Secured For Business Purpose [Member] | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	30
2019	537
2018	51
2017	69
2016	1,071
Prior	863
Revolving loans amortized cost basis	68
Total	2,689
Real Estate Residential Secured For Personal Purpose [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	117,318
2019	78,421
2018	67,071
2017	60,833
2016	46,982
Prior	102,772
Revolving loans amortized cost basis	1,291
Total	474,688
Real Estate Residential Secured For Personal Purpose [Member] | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
2020	117,318
2019	78,421
2018	67,015
2017	60,289
2016	46,982
Prior	100,749
Revolving loans amortized cost basis	1,291
Total	472,065
Real Estate Residential Secured For Personal Purpose [Member] | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	56
2017	544
2016	0
Prior	2,023
Revolving loans amortized cost basis	0
Total	2,623
Real Estate Home Equity Secured For Personal Purpose [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	1,002
2019	891
2018	1,282
2017	1,218
2016	588
Prior	2,669
Revolving loans amortized cost basis	164,798
Total	172,448
Real Estate Home Equity Secured For Personal Purpose [Member] | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
2020	1,002
2019	891
2018	1,179
2017	1,218
2016	588
Prior	2,627
Revolving loans amortized cost basis	163,942
Total	171,447
Real Estate Home Equity Secured For Personal Purpose [Member] | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	103
2017	0
2016	0
Prior	42
Revolving loans amortized cost basis	856
Total	1,001
Loans to Individuals [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	967
2019	1,747
2018	1,158
2017	532
2016	317
Prior	2,420
Revolving loans amortized cost basis	20,630
Total	27,771
Loans to Individuals [Member] | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
2020	967
2019	1,747
2018	1,158
2017	532
2016	317
Prior	2,397
Revolving loans amortized cost basis	20,630
Total	27,748
Loans to Individuals [Member] | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	23
Revolving loans amortized cost basis	0
Total	23
Lease Financings [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	53,992
2019	49,931
2018	35,072
2017	14,123
2016	5,504
Prior	913
Revolving loans amortized cost basis	0
Total	159,535
Lease Financings [Member] | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
2020	53,992
2019	49,890
2018	34,527
2017	13,866
2016	5,380
Prior	899
Revolving loans amortized cost basis	0
Total	158,554
Lease Financings [Member] | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	41
2018	545
2017	257
2016	124
Prior	14
Revolving loans amortized cost basis	0
Total	$ 981