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Description of Business and Summary of Significant Accounting Policies - Additional Information (Details) | 12 Months Ended |
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Dec. 31, 2022 USD ($) segment branch $ / shares | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Description Of Business And Summary Of Accounting Policies [Line Items] |  |  |
Number of reportable segments | segment | 2 |  |
Number of branches | branch | 14 |  |
Investment percentage in capital stock of FHLB, outstanding advances | 4.00% |  |
Investment percentage in capital stock of FHLB, total assets | 0.12% |  |
Federal home loan bank stock shares redeemed per share par value (in usd per share) | $ / shares | $ 1 |  |
Investment in federal home loan bank stock | $ 3,200,000 | $ 3,100,000 |
Reserve for unfunded commitments | 974,000 | 1,300,000 |
Unrecognized tax benefits | 0 | 0 |
Unrecognized tax benefits, income tax penalties and interest expense | 0 | 0 |
Advertising costs | $ 351,000 | 451,000 |
Minimum |  |  |
Description Of Business And Summary Of Accounting Policies [Line Items] |  |  |
Estimated useful lives of the assets | 3 years |  |
Maximum |  |  |
Description Of Business And Summary Of Accounting Policies [Line Items] |  |  |
Estimated useful lives of the assets | 39 years |  |
SBA and USDA |  |  |
Description Of Business And Summary Of Accounting Policies [Line Items] |  |  |
Loans held for sale | $ 0 | 0 |
SBA | Other Assets |  |  |
Description Of Business And Summary Of Accounting Policies [Line Items] |  |  |
Servicing assets | 183,000 |  |
USDA |  |  |
Description Of Business And Summary Of Accounting Policies [Line Items] |  |  |
Loans serviced | 14,300,000 | 19,300,000 |
USDA | Other Assets |  |  |
Description Of Business And Summary Of Accounting Policies [Line Items] |  |  |
Servicing assets |  | 269,000 |
Federal Reserve Bank Stock |  |  |
Description Of Business And Summary Of Accounting Policies [Line Items] |  |  |
Investment in federal reserve bank stock | 4,300,000 | 2,800,000 |
Pacific Coast Banker's Bancshares |  |  |
Description Of Business And Summary Of Accounting Policies [Line Items] |  |  |
Investment at cost | 100,000 | 100,000 |
Specialized Bank Technology Company |  |  |
Description Of Business And Summary Of Accounting Policies [Line Items] |  |  |
Investment at cost | 2,200,000 |  |
Unrealized holding gain on equity investment | 1,500,000 |  |
Technology Company |  |  |
Description Of Business And Summary Of Accounting Policies [Line Items] |  |  |
Unrealized loss (gain) on equity investment | 100,000 |  |
Equity investment, amount | 500,000 |  |
Equity investment, fair value | 0 | 100,000 |
Contribution of investments | 350,000 | 0 |
Investment Equity Funds |  |  |
Description Of Business And Summary Of Accounting Policies [Line Items] |  |  |
Contribution of investments | 349,000 | 163,000 |
Realized investment losses | 53,000 | 3,000 |
Equity interest investments | 456,000 | 160,000 | $ 0
Capital commitment of an investment | 988,000 |  |
CCBX Loans |  |  |
Description Of Business And Summary Of Accounting Policies [Line Items] |  |  |
Loans receivable | 152,500,000 |  |
Loans held for sale | $ 0 | $ 0 |

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- Definition This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(10)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 25 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8813-108599 + Details
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