Loans and Leases - Credit Quality (Details) $ in Thousands	Mar. 31, 2020 USD ($)
Commercial Financial And Agricultural [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	$ 52,867
2019	148,836
2018	102,598
2017	68,297
2016	36,501
Prior	92,297
Revolving loans amortized cost basis	442,793
Total	944,189
Commercial Financial And Agricultural [Member] | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	52,864
2019	146,722
2018	99,263
2017	65,395
2016	34,880
Prior	89,984
Revolving loans amortized cost basis	420,193
Total	909,301
Commercial Financial And Agricultural [Member] | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2020	3
2019	970
2018	1,979
2017	2,841
2016	1,621
Prior	1,685
Revolving loans amortized cost basis	9,678
Total	18,777
Commercial Financial And Agricultural [Member] | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	1,144
2018	1,356
2017	61
2016	0
Prior	628
Revolving loans amortized cost basis	12,922
Total	16,111
Real-Estate Commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	163,076
2019	626,616
2018	358,979
2017	369,421
2016	199,864
Prior	334,443
Revolving loans amortized cost basis	48,300
Total	2,100,699
Real-Estate Commercial [Member] | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	161,322
2019	613,240
2018	358,038
2017	357,068
2016	194,772
Prior	305,101
Revolving loans amortized cost basis	44,969
Total	2,034,510
Real-Estate Commercial [Member] | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2020	1,754
2019	12,432
2018	0
2017	1,134
2016	5,092
Prior	2,918
Revolving loans amortized cost basis	582
Total	23,912
Real-Estate Commercial [Member] | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	944
2018	941
2017	11,219
2016	0
Prior	26,424
Revolving loans amortized cost basis	2,749
Total	42,277
Real-Estate Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	42,483
2019	91,509
2018	62,849
2017	10,987
2016	2,950
Prior	0
Revolving loans amortized cost basis	4,372
Total	215,150
Real-Estate Construction [Member] | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	22,374
2019	91,509
2018	55,864
2017	10,987
2016	2,950
Prior	0
Revolving loans amortized cost basis	4,372
Total	188,056
Real-Estate Construction [Member] | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2020	20,109
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving loans amortized cost basis	0
Total	20,109
Real-Estate Construction [Member] | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	6,985
2017	0
2016	0
Prior	0
Revolving loans amortized cost basis	0
Total	6,985
Real Estate Residential Secured For Business Purpose [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	25,967
2019	88,461
2018	69,936
2017	56,552
2016	50,042
Prior	56,816
Revolving loans amortized cost basis	29,870
Total	377,644
Real Estate Residential Secured For Business Purpose [Member] | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	24,846
2019	87,962
2018	69,936
2017	56,391
2016	48,747
Prior	55,682
Revolving loans amortized cost basis	29,802
Total	373,366
Real Estate Residential Secured For Business Purpose [Member] | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2020	1,121
2019	475
2018	0
2017	79
2016	743
Prior	480
Revolving loans amortized cost basis	0
Total	2,898
Real Estate Residential Secured For Business Purpose [Member] | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	24
2018	0
2017	82
2016	552
Prior	654
Revolving loans amortized cost basis	68
Total	1,380
Real Estate Residential Secured For Personal Purpose [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	27,745
2019	94,178
2018	87,486
2017	71,235
2016	53,602
Prior	119,081
Revolving loans amortized cost basis	1,671
Total	454,998
Real Estate Residential Secured For Personal Purpose [Member] | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
2020	27,745
2019	93,752
2018	87,429
2017	71,235
2016	53,602
Prior	117,858
Revolving loans amortized cost basis	1,671
Total	453,292
Real Estate Residential Secured For Personal Purpose [Member] | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	426
2018	57
2017	0
2016	0
Prior	1,223
Revolving loans amortized cost basis	0
Total	1,706
Real Estate Home Equity Secured For Personal Purpose [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	164
2019	1,104
2018	1,815
2017	1,702
2016	692
Prior	3,613
Revolving loans amortized cost basis	168,315
Total	177,405
Real Estate Home Equity Secured For Personal Purpose [Member] | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
2020	164
2019	1,104
2018	1,707
2017	1,702
2016	692
Prior	3,583
Revolving loans amortized cost basis	167,579
Total	176,531
Real Estate Home Equity Secured For Personal Purpose [Member] | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	108
2017	0
2016	0
Prior	30
Revolving loans amortized cost basis	736
Total	874
Loans to Individuals [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	630
2019	2,282
2018	1,464
2017	821
2016	481
Prior	2,799
Revolving loans amortized cost basis	20,693
Total	29,170
Loans to Individuals [Member] | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
2020	630
2019	2,282
2018	1,464
2017	821
2016	481
Prior	2,736
Revolving loans amortized cost basis	20,693
Total	29,107
Loans to Individuals [Member] | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	63
Revolving loans amortized cost basis	0
Total	63
Lease Financings [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	15,187
2019	58,697
2018	43,716
2017	19,878
2016	9,531
Prior	2,561
Revolving loans amortized cost basis	0
Total	149,570
Lease Financings [Member] | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
2020	15,187
2019	58,670
2018	43,587
2017	19,482
2016	9,488
Prior	2,495
Revolving loans amortized cost basis	0
Total	148,909
Lease Financings [Member] | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	27
2018	129
2017	396
2016	43
Prior	66
Revolving loans amortized cost basis	0
Total	$ 661