Loans and Allowance for Credit Losses - Summary of Aging of Past Due Originated and ANCI Loans by Portfolio Segment and Class of Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Accruing Loans | 30-59 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	$ 10,678	$ 1,913
Accruing Loans | 60-89 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	2,613	513
Accruing Loans | 90+DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	11,639	760
Non-Accruing Loans | 30-59 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	388	356
Non-Accruing Loans | 60-89 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due		99
Non-Accruing Loans | 90+DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	8,775	1,479
Non-Accruing Loans | 0-29 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	68,520	72,305
Commercial and Industrial | Accruing Loans | 30-59 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	516	120
Commercial and Industrial | Accruing Loans | 90+DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	10,029
Commercial and Industrial | Non-Accruing Loans | 30-59 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due		176
Commercial and Industrial | Non-Accruing Loans | 90+DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	7,877
Commercial and Industrial | Non-Accruing Loans | 0-29 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	66,780	71,179
Commercial and Industrial | General C&I | Accruing Loans | 30-59 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	516	120
Commercial and Industrial | General C&I | Accruing Loans | 90+DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	10,029
Commercial and Industrial | General C&I | Non-Accruing Loans | 30-59 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due		176
Commercial and Industrial | General C&I | Non-Accruing Loans | 0-29 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	34,459	23,928
Commercial and Industrial | Restaurant Industry | Non-Accruing Loans | 0-29 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	21,869	22,043
Commercial and Industrial | Healthcare | Non-Accruing Loans | 0-29 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	4,449	4,496
Commercial and Industrial | Energy Sector | Non-Accruing Loans | 90+DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	7,877
Commercial and Industrial | Energy Sector | Non-Accruing Loans | 0-29 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	6,003	20,712
Commercial Real Estate | Accruing Loans | 30-59 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	1,120
Commercial Real Estate | Accruing Loans | 60-89 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due		61
Commercial Real Estate | Land and Development | Accruing Loans | 30-59 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	1,120
Commercial Real Estate | Land and Development | Accruing Loans | 60-89 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due		61
Consumer | Accruing Loans | 30-59 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	3,946	1,302
Consumer | Accruing Loans | 60-89 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	1,645	427
Consumer | Accruing Loans | 90+DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	1,610	760
Consumer | Accruing Loans | Residential Real Estate | 30-59 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	2,849	1,275
Consumer | Accruing Loans | Residential Real Estate | 60-89 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	1,372	315
Consumer | Accruing Loans | Residential Real Estate | 90+DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	1,604	760
Consumer | Accruing Loans | Other | 30-59 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	1,097	27
Consumer | Accruing Loans | Other | 60-89 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	273	112
Consumer | Accruing Loans | Other | 90+DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	6
Consumer | Non-Accruing Loans | 30-59 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	353	151
Consumer | Non-Accruing Loans | 60-89 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due		95
Consumer | Non-Accruing Loans | 90+DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	815	1,429
Consumer | Non-Accruing Loans | 0-29 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	1,408	876
Consumer | Non-Accruing Loans | Residential Real Estate | 30-59 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	353	151
Consumer | Non-Accruing Loans | Residential Real Estate | 60-89 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due		95
Consumer | Non-Accruing Loans | Residential Real Estate | 90+DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	815	1,429
Consumer | Non-Accruing Loans | Residential Real Estate | 0-29 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	1,408	876
Small Business Lending | Accruing Loans | 30-59 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	5,096	491
Small Business Lending | Accruing Loans | 60-89 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	968	25
Small Business Lending | Non-Accruing Loans | 30-59 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	35	29
Small Business Lending | Non-Accruing Loans | 60-89 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due		4
Small Business Lending | Non-Accruing Loans | 90+DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	83	50
Small Business Lending | Non-Accruing Loans | 0-29 DPD
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Past Due	$ 332	$ 250