| Liquidity - Additional Information (Detail) - Hanmi Bank - USD ($) $ in Millions | Mar. 31, 2020 | Dec. 31, 2019 | 
|---|---|---|
| Line of Credit Facility [Line Items] | ||
| Cash on deposit with bank subsidiary | $ 20.0 | |
| Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances | 300.0 | $ 90.0 | 
| Broker deposits | $ 224.6 | 264.2 | 
| Percentage of borrowings from FHLB (up to) | 30.00% | |
| Borrowing capacity available based on pledged collateral | $ 1,220.0 | $ 878.4 | 
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- Definition Federal home loan bank advances maximum borrowing capacity as percentage of assets. No definition available. 
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- Definition A bank's noninterest bearing demand deposits in other banks (such as correspondents). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of advances from the Federal Home Loan Bank (FHLB). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of right to receive cash and securities on deposit with broker-dealers to demonstrate an intention to complete a purchase (good faith deposit) and collateral deposited by counterparty to cover the credit risk assumed (margin deposit). No definition available. 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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- Details 
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