Loans and Allowance For Loan Losses - Summary of Loan Portfolio Allocated by Management's Internal Risk Ratings (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	$ 1,299,481	$ 949,652
Commercial And Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	365,881	389,746
Real Estate Construction And Land [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	49,524	42,519
SBA [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	373,429	12,830
Other Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	1,731	1,628
Loans Receivable [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	1,299,481	949,652
Loans Receivable [Member] | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	1,270,620	925,736
Loans Receivable [Member] | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	13,598	18,265
Loans Receivable [Member] | Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	15,263	5,651
Loans Receivable [Member] | Commercial And Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	365,881	389,746
Loans Receivable [Member] | Commercial And Industrial [Member] | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	351,053	378,327
Loans Receivable [Member] | Commercial And Industrial [Member] | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	6,807	6,894
Loans Receivable [Member] | Commercial And Industrial [Member] | Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	8,021	4,525
Loans Receivable [Member] | Real Estate, Other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	508,916	502,929
Loans Receivable [Member] | Real Estate, Other [Member] | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	499,176	494,314
Loans Receivable [Member] | Real Estate, Other [Member] | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	5,184	7,928
Loans Receivable [Member] | Real Estate, Other [Member] | Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	4,556	687
Loans Receivable [Member] | Real Estate Construction And Land [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	49,524	42,519
Loans Receivable [Member] | Real Estate Construction And Land [Member] | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	47,746	40,731
Loans Receivable [Member] | Real Estate Construction And Land [Member] | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure		1,788
Loans Receivable [Member] | Real Estate Construction And Land [Member] | Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	1,778
Loans Receivable [Member] | SBA [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	373,429	12,830
Loans Receivable [Member] | SBA [Member] | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	370,914	10,736
Loans Receivable [Member] | SBA [Member] | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	1,607	1,655
Loans Receivable [Member] | SBA [Member] | Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	908	439
Loans Receivable [Member] | Other Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	1,731	1,628
Loans Receivable [Member] | Other Loans [Member] | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Credit Exposure	$ 1,731	$ 1,628