v3.25.3

DEPOSITS - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Deposit Liability [Line Items]
Deposit contracts, liabilities	$ 5,000.0
ICS deposits	$ 770.3	$ 754.4
Percent of total deposits	22.30%	22.20%
Percentage of bank liabilities	0.219
Time deposits exceeding FDIC insurance limit	$ 66.7	$ 80.6
Brokered time deposits	3.8	121.1
Asset Pledged as Collateral \| Letter of Credit
Deposit Liability [Line Items]
Collateralized deposits	$ 23.3	$ 25.1

Deposits, Interest-Bearing Money Market Deposits And Savings Account Deposits, Insured Cash Sweep

+ References

No definition available.

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- Definition

Percentage Of Interest-Bearing Domestic Deposits To Bank Liabilities

+ References

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- Definition

Carrying amount of liabilities as of the balance sheet date pertaining to amounts received by the insurer or reinsurer from the insured (including a ceding company) under insurance or reinsurance contracts for which insurance risk is not transferred.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 340
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483081/340-30-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 340
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483054/340-30-50-1

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1406
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-Publisher SEC

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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The aggregate fair value as of the balance sheet date of financial instruments and other positions owned by the entity including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. Includes both pledged and unpledged holdings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 940
-SubTopic 320
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479035/940-320-45-2

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- Definition

Amount of interest-bearing domestic third-party deposits placed by or through the assistance of a deposit broker, also known as brokered deposit liabilities.

+ References

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-Topic 942
-SubTopic 210
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- Definition

Percentage of interest-bearing domestic deposit liabilities to total deposit liabilities.

+ References

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations that meet or exceed the Federal Deposit Insurance Corporation (FDIC) insurance limit.

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-Name Accounting Standards Codification
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California BanCorp \ CA 10-Q