Alternative Investments, Unfunded Investment Commitments

No definition available.

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Namespace Prefix:	banc_
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Balance Type:	credit
Period Type:	instant

- Definition

Nominal or face amount used to calculate payments on the derivative asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
-Section S99
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-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 320
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-Section S99
-Paragraph 5C
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480032/946-320-S99-5C

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 320
-Name Accounting Standards Codification
-Section S99
-Paragraph 5A
-Subparagraph (SX 210.12-13A(Column D))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480032/946-320-S99-5A

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 320
-Name Accounting Standards Codification
-Section S99
-Paragraph 5B
-Subparagraph (SX 210.12-13B(Column B))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480032/946-320-S99-5B

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
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-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

Reflects the amount of cash required to fully fund agreements to provide advances to borrowers and lessees at stated interest rates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
-Section 50
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-Publisher FASB
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-URI https://asc.fasb.org//1943274/2147480981/942-825-50-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Reflects the amount of cash required to fully fund agreements to provide advances to borrowers and lessees at interest rates that increase or decrease depending on certain facts or circumstances.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_UnusedLinesOfCreditMember
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- Details

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LOAN COMMITMENTS AND OTHER RELATED ACTIVITIES - Contractual Amount of Financial Instruments with Off-Balance-Sheet Risk (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022	Jul. 25, 2023
Other Commitments [Line Items]
Unfunded commitment	$ 15,350	$ 17,480
Derivatives asset, notional amount	5,233,632	39,579
Contingent forward loan sale agreement
Other Commitments [Line Items]
Derivatives asset, notional amount	1,803,869	0	$ 1,800,000
LIHTC Investments
Other Commitments [Line Items]
Unfunded commitment	15,400	17,500
Small Business Investment Companies
Other Commitments [Line Items]
Unfunded commitment	7,400	8,600
Other Investments
Other Commitments [Line Items]
Unfunded commitment	20,500	9,800
Commitments to extend credit
Other Commitments [Line Items]
Fixed Rate	65,639	50,193
Variable Rate	164,455	180,696
Unused lines of credit
Other Commitments [Line Items]
Fixed Rate	46,747	8,392
Variable Rate	1,365,588	1,505,122
Letters of credit
Other Commitments [Line Items]
Fixed Rate	1,673	2,461
Variable Rate	$ 8,886	$ 7,016