Loans - Components of loans (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Components of loans
Total Loans, Gross	$ 1,912,038	$ 1,664,931
Allowance for Loan Losses	(22,526)	(20,031)	$ (16,502)	$ (12,333)
Net Deferred Loan Fees	(5,512)	(4,515)
Total Loans, Net	1,884,000	1,640,385
Commercial
Components of loans
Total Loans, Gross	276,035	260,833
Allowance for Loan Losses	(3,058)	(2,898)	(2,435)	(1,315)
Construction and Land Development
Components of loans
Total Loans, Gross	196,776	210,041
Allowance for Loan Losses	(2,202)	(2,451)	(1,892)	(1,379)
Real Estate Mortgage
Components of loans
Total Loans, Gross	1,434,754	1,189,797
1-4 Family Mortgage
Components of loans
Total Loans, Gross	260,611	226,773
Allowance for Loan Losses	(2,839)	(2,597)	(2,317)	(2,410)
Multifamily
Components of loans
Total Loans, Gross	515,014	407,934
Allowance for Loan Losses	(5,824)	(4,644)	(3,170)	(1,568)
CRE Owner Occupied
Components of loans
Total Loans, Gross	66,584	64,458
Allowance for Loan Losses	(792)	(808)	(956)	(1,160)
CRE Non-owner Occupied
Components of loans
Total Loans, Gross	592,545	490,632
Allowance for Loan Losses	(6,972)	(5,872)	(5,087)	(3,323)
Consumer and other
Components of loans
Total Loans, Gross	4,473	4,260
Allowance for Loan Losses	$ (85)	$ (65)	$ (60)	$ (78)

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 of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts 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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