BORROWINGS - Federal Home Loan Bank (Details) - Federal Home Loan Bank of San Francisco [Member] - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2021	May 31, 2020
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances	$ 0	$ 10,000
Federal Home Loan Bank of San Francisco, Secured Borrowing Facility [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, General Description of Terms	Bank has an approved secured borrowing facility with the Federal Home Loan Bank of San Francisco (the “FHLB”) for up to 25% of total assets for a term not to exceed five years under a blanket lien of certain types of loans.
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Percentage of Total Assets	25.00%
Debt Instrument, Term	5 years
Federal Home Loan Bank of San Francisco, Advance, Maturing November 9, 2020 [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances		5,000
Federal Home Loan Bank of San Francisco, Advance, Maturing May 7, 2021 [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances		$ 5,000

Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Percentage of Total Assets

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Amount of advances from the Federal Home Loan Bank (FHLB).

+ References

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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.

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- Definition

Describes the general term and nature of the advances from the Federal Home Loan Bank outstanding as of the Balance Sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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