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Loans - Components of loans (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Components of loans
Total Loans, Gross	$ 2,193,778		$ 1,912,038
Allowance for Loan Losses	(27,633)	$ (24,585)	(22,526)	$ (21,362)	$ (20,607)	$ (20,031)
Net Deferred Loan Fees	(10,287)		(5,512)
Total Loans, Net	2,155,858		1,884,000
Commercial
Components of loans
Total Loans, Gross	302,536		276,035
Allowance for Loan Losses	(5,192)	(3,557)	(3,058)	(3,181)	(3,361)	(2,898)
Paycheck Protection Program (PPP)
Components of loans
Total Loans, Gross	180,228
Allowance for Loan Losses	(90)
Construction and Land Development
Components of loans
Total Loans, Gross	191,768		196,776
Allowance for Loan Losses	(2,173)	(2,131)	(2,202)	(2,246)	(2,097)	(2,451)
Real Estate Mortgage
Components of loans
Total Loans, Gross	1,513,137		1,434,754
1-4 Family Mortgage
Components of loans
Total Loans, Gross	289,456		260,611
Allowance for Loan Losses	(3,322)	(3,202)	(2,839)	(2,827)	(2,611)	(2,597)
Multifamily
Components of loans
Total Loans, Gross	522,491		515,014
Allowance for Loan Losses	(6,697)	(6,556)	(5,824)	(4,994)	(4,715)	(4,644)
CRE Owner Occupied
Components of loans
Total Loans, Gross	73,539		66,584
Allowance for Loan Losses	(964)	(938)	(792)	(844)	(790)	(808)
CRE Non-owner Occupied
Components of loans
Total Loans, Gross	627,651		592,545
Allowance for Loan Losses	(8,323)	(8,003)	(6,972)	(6,485)	(6,349)	(5,872)
Consumer and other
Components of loans
Total Loans, Gross	6,109		4,473
Allowance for Loan Losses	$ (174)	$ (92)	$ (85)	$ (66)	$ (61)	$ (65)