Loans - Composition of Loan Portfolio (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	$ 913,064	$ 875,059
Allowance for loan losses	(9,619)	(9,636)
Loans receivable, net	903,445	865,423
Real Estate
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	666,141	621,668
Real Estate \| Commercial Real Estate
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	545,481	503,834
Real Estate \| SBA Loans—Real Estate
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	120,660	117,834
SBA Loans—Non-Real Estate
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	9,818	9,541
Commercial and Industrial
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	106,796	113,975
Home Mortgage
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	127,851	127,298
Consumer
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	$ 2,458	$ 2,577

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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