Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net income	$ 15,730	$ 7,344	$ 5,259
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan and lease losses		950
Provision for depreciation and amortization	1,738	2,061	1,908
Amortization of core deposit intangible	221	221	185
Amortization of debt issuance costs	48	45	40
Compensation expense associated with stock options	8	23	24
Compensation expense associated with restricted stock	288	273	215
Tax benefits from vesting of restricted stock	(46)	(53)
Net gains on sale or call of securities	(44)	(137)	(244)
Other-than-temporary impairment on investment securities	0	0	546
Amortization of investment premiums and accretion of discounts, net	1,845	2,031	1,715
Accretion of held-to-maturity fair value adjustments		(56)	(97)
Loss on cancellation of interest rate swap			2,325
Write-down of other real estate owned		52	66
(Gain) loss on sale of other real estate owned	(73)	(368)	109
Increase in cash surrender value of life insurance	(512)	(548)	(613)
Life insurance death benefit		(502)
Increase (decrease) in deferred compensation and salary continuation plans	67	18	(19)
Increase in deferred loan fees and costs	(217)	(386)	(454)
Decrease in deferred income taxes	595	271	132
Deferred tax asset write-down		2,490	363
(Increase) decrease in other assets	(10)	863	118
Increase (decrease) in other liabilities	1,094	(961)	306
Net cash provided by operating activities	20,732	13,631	11,884
Cash flows from investing activities:
Proceeds from maturities and payments of available-for-sale securities	31,538	23,551	31,685
Proceeds from sale of available-for-sale securities	30,235	64,349	51,025
Purchases of available-for-sale securities	(57,616)	(150,888)	(104,134)
Proceeds from maturities and payments of held-to-maturity securities		1,098	4,963
Investment in Qualified Zone Academy Bonds		(1,000)	(2,000)
Investment in qualified affordable housing partnerships	(38)	(124)	(697)
Net purchase of Federal Home Loan Bank of San Francisco stock	(1,355)	(72)
Loan originations, net of principal repayments	(57,690)	(76,016)	(105,892)
Net (purchase of) repayment on purchased loans	(8,499)	(1,158)	18,666
Purchase of premises and equipment	(351)	(584)	(2,873)
Proceeds from the sale of other real estate owned	217	2,111	636
Proceeds from life insurance policy		2,249
Payments to derivative counterparties for the termination of interest rate swaps			(2,578)
Acquisition of branches, net of cash paid			142,411
Net cash (used) provided by investing activities	(63,559)	(136,484)	31,212
Cash flows from financing activities:
Net increase in demand deposits, money market accounts and savings accounts	65,857	124,201	84,722
Net decrease in certificates of deposit	(36,873)	(26,135)	(32,838)
Advances on term debt	230,160	30,260	55,000
Repayment of term debt	(233,761)	(32,080)	(131,172)
Proceeds from stock options exercised	216	245	10
Net proceeds from issuance of common stock		26,778
Cash paid for shares surrendered for tax-withholding purposes	(103)	(77)
Cash dividends paid on common stock	(2,274)	(1,776)	(1,603)
Net cash provided by (used in) financing activities	23,222	121,416	(25,881)
Net (decrease) increase cash and cash equivalents	(19,605)	(1,437)	17,215
Cash and cash equivalents at the beginning of year	66,970	68,407	51,192
Cash and cash equivalents at the end of year	47,365	66,970	68,407
Cash paid during the period for:
Income taxes	2,727	3,846	2,705
Interest	5,171	4,581	5,142
Supplemental disclosures of non cash investing activities:
Transfer of loans to other real estate owned	140	981	147
Changes in unrealized (loss) gain on investment securities available-for-sale	(3,818)	892	(2,964)
Changes in net deferred tax asset related to changes in unrealized loss (gain) on investment securities available-for-sale	1,128	(368)	1,220
Changes in accumulated other comprehensive (loss) income due to changes in unrealized (loss) gain on investment securities available-for-sale	(2,690)	524	(1,744)
Accretion of held-to-maturity fair value adjustment from other comprehensive income to interest income		(56)	(97)
Changes in deferred tax related to accretion of held-to-maturity investment securities		23
Changes in accumulated other comprehensive income (loss) due to accretion of held-to-maturity investment securities		(33)	(97)
Fair value adjustment for held to maturities securities transferred to available-for-sale		(167)
Changes in deferred tax related to transfer of held-to-maturity investment securities to available-for-sale		69
Net fair value adjustment for held-to-maturity securities transferred to available-for-sale		(98)
Changes in accumulated other comprehensive income (loss) related held-to-maturity investment securities		(131)	(97)
Reclassification of accumulated other comprehensive income due to tax rate change	52
Changes in unrealized loss on derivatives			(348)
Changes in net deferred tax asset related to changes in unrealized loss on derivatives			143
Changes in accumulated other comprehensive income (loss) due to changes in unrealized loss on derivatives			(205)
Reclassification of losses on derivatives			2,721
Changes in net deferred tax asset related to reclassification of losses on derivatives			(1,120)
Changes in accumulated other comprehensive income (loss) due to reclassification of losses on derivatives			1,601
Supplemental disclosures of non cash financing activities:
Vested and granted restricted stock issued under employee plans			84
Stock issued under employee plans	45	41
Transfer of investment securities from HTM to AFS		30,330
Cash dividend declared on common stock and payable after period-end	651	486	401
Transactions Related to Acquisition:
Assets acquired - fair value			155,230
Goodwill			665
Liabilities assumed - fair value			$ 149,239