Loans and Leases Held for Investment and Credit Quality - Summary of Risk Grades of Each Category of Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	$ 2,639,840	$ 1,850,480
Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	894,997	618,748
Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	347,318	248,904
Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	1,052,793	739,030
Commercial Land
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	344,732	243,798
Healthcare | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	45,581	51,082
Healthcare | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	94,742	81,619
Healthcare | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	247,625	188,531
Risk Grades 1 - 4
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	2,369,552	1,702,491
Risk Grades 1 - 4 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	810,864	559,716
Risk Grades 1 - 4 | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	331,135	247,099
Risk Grades 1 - 4 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	921,507	671,850
Risk Grades 1 - 4 | Commercial Land
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	306,046	223,826
Risk Grades 1 - 4 | Healthcare | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	36,151	38,908
Risk Grades 1 - 4 | Healthcare | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	90,454	79,814
Risk Grades 1 - 4 | Healthcare | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	201,322	161,026
Risk Grade 5
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	149,954	65,484
Risk Grade 5 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	52,577	30,770
Risk Grade 5 | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	15,477	1,805
Risk Grade 5 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	71,782	23,995
Risk Grade 5 | Commercial Land
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	10,118	8,914
Risk Grade 5 | Healthcare | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	1,429	2,502
Risk Grade 5 | Healthcare | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	3,582	1,805
Risk Grade 5 | Healthcare | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	16,740	7,696
Risk Grades 6 - 8
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	120,334	82,505
Risk Grades 6 - 8 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	31,556	28,262
Risk Grades 6 - 8 | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	706
Risk Grades 6 - 8 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	59,504	43,185
Risk Grades 6 - 8 | Commercial Land
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	28,568	11,058
Risk Grades 6 - 8 | Healthcare | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	8,001	9,672
Risk Grades 6 - 8 | Healthcare | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	706
Risk Grades 6 - 8 | Healthcare | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	29,563	19,809
Agricultural | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	9,344	6,400
Agricultural | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	44,571	43,454
Agricultural | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	50,365	53,085
Agricultural | Commercial Land
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	344,732	243,798
Agricultural | Risk Grades 1 - 4 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	8,684	6,187
Agricultural | Risk Grades 1 - 4 | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	44,571	43,454
Agricultural | Risk Grades 1 - 4 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	47,187	52,518
Agricultural | Risk Grades 1 - 4 | Commercial Land
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	306,046	223,826
Agricultural | Risk Grade 5 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	219	213
Agricultural | Risk Grade 5 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	1,093	567
Agricultural | Risk Grade 5 | Commercial Land
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	10,118	8,914
Agricultural | Risk Grades 6 - 8 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	441
Agricultural | Risk Grades 6 - 8 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	2,085
Agricultural | Risk Grades 6 - 8 | Commercial Land
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	28,568	11,058
Funeral Home & Cemetery | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	26,388	17,378
Funeral Home & Cemetery | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	9,033	9,874
Funeral Home & Cemetery | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	113,517	71,344
Funeral Home & Cemetery | Risk Grades 1 - 4 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	24,446	17,085
Funeral Home & Cemetery | Risk Grades 1 - 4 | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	9,033	9,874
Funeral Home & Cemetery | Risk Grades 1 - 4 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	105,753	64,487
Funeral Home & Cemetery | Risk Grade 5 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	1,942	287
Funeral Home & Cemetery | Risk Grade 5 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	5,987	3,711
Funeral Home & Cemetery | Risk Grades 6 - 8 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases		6
Funeral Home & Cemetery | Risk Grades 6 - 8 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	1,777	3,146
Independent Pharmacies | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	106,096	108,783
Independent Pharmacies | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	443	2,149
Independent Pharmacies | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	26,379	20,597
Independent Pharmacies | Risk Grades 1 - 4 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	92,964	93,976
Independent Pharmacies | Risk Grades 1 - 4 | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	443	2,149
Independent Pharmacies | Risk Grades 1 - 4 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	16,385	12,509
Independent Pharmacies | Risk Grade 5 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	6,986	5,734
Independent Pharmacies | Risk Grade 5 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	2,037	2,495
Independent Pharmacies | Risk Grades 6 - 8 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	6,146	9,073
Independent Pharmacies | Risk Grades 6 - 8 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	7,957	5,593
Registered Investment Advisors | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	99,191	94,338
Registered Investment Advisors | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	2,404	1,232
Registered Investment Advisors | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	7,431	7,905
Registered Investment Advisors | Risk Grades 1 - 4 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	95,613	88,614
Registered Investment Advisors | Risk Grades 1 - 4 | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	2,404	1,232
Registered Investment Advisors | Risk Grades 1 - 4 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	7,431	7,780
Registered Investment Advisors | Risk Grade 5 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	2,066	2,381
Registered Investment Advisors | Risk Grade 5 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases		125
Registered Investment Advisors | Risk Grades 6 - 8 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	1,512	3,343
Veterinary Industry | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	51,251	45,604
Veterinary Industry | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	22,132	14,094
Veterinary Industry | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	146,319	136,721
Veterinary Industry | Risk Grades 1 - 4 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	46,936	42,175
Veterinary Industry | Risk Grades 1 - 4 | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	22,132	14,094
Veterinary Industry | Risk Grades 1 - 4 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	127,893	117,879
Veterinary Industry | Risk Grade 5 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	1,718	1,190
Veterinary Industry | Risk Grade 5 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	8,671	4,205
Veterinary Industry | Risk Grades 6 - 8 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	2,597	2,239
Veterinary Industry | Risk Grades 6 - 8 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	9,755	14,637
Other Industries | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	557,146	295,163
Other Industries | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	173,993	96,482
Other Industries | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	461,157	260,847
Other Industries | Risk Grades 1 - 4 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	506,070	272,771
Other Industries | Risk Grades 1 - 4 | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	162,098	96,482
Other Industries | Risk Grades 1 - 4 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	415,536	255,651
Other Industries | Risk Grade 5 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	38,217	18,463
Other Industries | Risk Grade 5 | Construction & Development
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	11,895
Other Industries | Risk Grade 5 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	37,254	5,196
Other Industries | Risk Grades 6 - 8 | Commercial & Industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	12,859	$ 3,929
Other Industries | Risk Grades 6 - 8 | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	$ 8,367