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Allowance for Credit Losses on Loans - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Changes in California Unemployment and Gross Domestic Product |  |  |  |
Loans and Leases Receivable Disclosure [Line Items] |  |  |  |
Increase in credit reserve on loans | $ 19,143 |  |  |
Financial Asset Originated |  |  |  |
Loans and Leases Receivable Disclosure [Line Items] |  |  |  |
Interest income on non accrual loans | 428 | $ 449 | $ 859 | $ 849
Interest income recognized on non accrual loans | $ 39 | $ 164 | $ 86 | $ 257

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- Definition Interest income recognized on nonaccrual loans. + References No definition available. + Details
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Balance Type: | credit
Period Type: | duration

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- Definition Amount of increase (decrease) in allowance for credit loss on financing receivable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447 + Details
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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. + References No definition available. + Details
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- Definition Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18794-111554 + Details
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Balance Type: | credit
Period Type: | duration

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- Details
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