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Summary of Significant Accounting Policies - Additional Information (Details) |  | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
May 24, 2021 USD ($) | Dec. 31, 2021 USD ($) branch | Dec. 31, 2020 USD ($) | Jun. 30, 2021 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |  |
Number of full service branches | branch |  | 9 |  |  |  |
Loans |  | $ 1,297,896,000 | $ 1,084,384,000 |  |  |
Servicing assets |  | 12,720,000 | 7,360,000 |  |  |
Accrued interest receivable |  | 4,579,000 | 3,985,000 |  |  |
Loans receivable, allowance |  | 16,123,000 | 15,352,000 |  | $ 10,050,000 | $ 9,636,000
Interest and/or penalties related to income tax matters |  | $ 0 | $ 0 |  |  |
Hana Small Business Lending Inc |  |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |  |
Payments to purchase loan portfolio | $ 97,631,000 |  |  |  |  |
Loans | 100,003,000 |  |  |  |  |
Fair value discount of loans | 8,867,000 |  |  |  |  |
Servicing assets | 6,097,000 |  |  |  |  |
Accrued interest receivable | $ 398,000 |  |  |  |  |
Hana Small Business Lending Inc | Purchased Performing Loans |  |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |  |
Loans receivable, allowance |  |  |  | $ 0 |  |
Equipment and Furnishings | Minimum |  |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |  |
Equipment and furnishings, useful lives |  | 3 years |  |  |  |
Equipment and Furnishings | Maximum |  |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |  |
Equipment and furnishings, useful lives |  | 10 years |  |  |  |
Open Bank |  |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |  |
Percentage of voting equity interests acquired |  | 100.00% |  |  |  |

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