Consolidated Statements of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Interest income:
Interest and fees on loans		$ 12,847	$ 11,164	$ 24,878	$ 21,893
Interest on taxable securities		1,733	1,278	3,497	2,487
Interest on tax-exempt securities		328	413	715	876
Interest on interest-bearing deposits in other banks		219	135	464	264
Total interest income		15,127	12,990	29,554	25,520
Interest expense:
Interest on demand - interest-bearing		129	80	255	169
Interest on money market		380	135	669	267
Interest on savings		123	64	234	123
Interest on certificates of deposit		497	488	987	983
Interest on Federal Home Loan Bank of San Francisco borrowings		192	267	247	314
Interest on other borrowings		201	279	440	560
Interest on junior subordinated debentures		110	97	223	179
Total interest expense		1,632	1,410	3,055	2,595
Net interest income		13,495	11,580	26,499	22,925
Provision for loan and lease losses
Net interest income after provision for loan and lease losses		13,495	11,580	26,499	22,925
Noninterest income:
Fees on payroll and benefit processing		157	146	328	315
Life insurance		155	127	284	256
Gain on sale of investment securities, net		33	4	125	40
Federal Home Loan Bank of San Francisco dividends		124	95	245	175
Gain on sale of OREO		18		41	16
Other income		108	115	196	225
Total noninterest income		1,100	962	2,157	1,944
Noninterest expense:
Salaries and related benefits		5,146	4,513	10,875	9,368
Premises and equipment		945	1,016	1,937	2,087
Federal Deposit Insurance Corporation insurance premium		95	93	195	189
Data processing fees		621	471	1,180	903
Professional service fees		535	314	838	659
Telecommunications		180	178	353	394
Acquisition costs		376		2,306
Other expenses		1,713	1,086	2,850	2,104
Total noninterest expense		9,611	7,671	20,534	15,704
Income before provision for income taxes		4,984	4,871	8,122	9,165
Provision for income taxes		1,340	1,253	2,172	2,306
Net income		$ 3,644	$ 3,618	$ 5,950	$ 6,859
Earnings per share - basic (in dollars per share)		$ 0.20	$ 0.22	$ 0.33	$ 0.42
Weighted average shares - basic (in shares)	[1]	18,134	16,245	17,816	16,237
Earnings per share - diluted (in dollars per share)		$ 0.20	$ 0.22	$ 0.33	$ 0.42
Weighted average shares - diluted (in shares)		18,194	16,325	17,878	16,319
Deposit Account [Member]
Noninterest income:
Revenue from Contract with Customer		$ 187	$ 175	$ 355	$ 351
Credit and Debit Card [Member]
Noninterest income:
Revenue from Contract with Customer		$ 318	$ 300	$ 583	$ 566

[1] Excludes unvested restricted shares because they do not have dividend or voting rights