Depository Shares Issued

No definition available.

Name:	banc_DepositorySharesIssued
Namespace Prefix:	banc_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Depository Shares Issued, Price Per Share

+ References

No definition available.

+ Details

Name:	banc_DepositorySharesIssuedPricePerShare
Namespace Prefix:	banc_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Depository Shares to Preferred Stock Ratio

+ References

No definition available.

+ Details

Name:	banc_DepositorySharesToPreferredStockRatio
Namespace Prefix:	banc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Related Party Transaction, Expenses from Transactions with Related Party, Net

+ References

No definition available.

+ Details

Name:	banc_RelatedPartyTransactionExpensesfromTransactionswithRelatedPartyNet
Namespace Prefix:	banc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Related Party Transaction, Strategic Advisor Agreement, Period

+ References

No definition available.

+ Details

Name:	banc_RelatedPartyTransactionStrategicAdvisorAgreementPeriod
Namespace Prefix:	banc_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of days the underwriters have the option to exercise their overallotment option from the closing date.

+ References

No definition available.

+ Details

Name:	banc_UnderwritersOverallotmentOptionPeriod
Namespace Prefix:	banc_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage rate used to calculate dividend payments on preferred stock.

+ References

No definition available.

+ Details

Name:	us-gaap_PreferredStockDividendRatePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Value of the difference between preference in liquidation and the par or stated values of the preferred shares.

+ References

No definition available.

+ Details

Name:	us-gaap_PreferredStockLiquidationPreferenceValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

+ Details

Name:	us-gaap_RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

Name:	us-gaap_RelatedPartyTransactionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of new stock issued during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

+ Details

Name:	us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_StatementClassOfStockAxis=us-gaap_SeriesDPreferredStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=banc_FivePointTwoFivePercentSeniorNotesDueApril152025Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_DirectorMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=banc_UnderwritingFeesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=banc_FormerChairmanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=banc_FormerManagementMemberMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=banc_UnderwrittenPublicOfferingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=us-gaap_OverAllotmentOptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_CommonStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

RELATED-PARTY TRANSACTIONS - Transaction Involving Halle Benett and Former Chairman Timothy R. Chrisman (Details) - USD ($)					6 Months Ended
	Apr. 08, 2015	Apr. 06, 2015	May. 21, 2014	May. 15, 2014	Jun. 30, 2015
Related Party Transaction [Line Items]
Underwriters option period	30 days
Series D Preferred Stock
Related Party Transaction [Line Items]
Depository shares to preferred stock ratio	2.50%
Non cumulative preferred stock, dividend rate	7.375%				7.375%
Price per share of depository shares (in usd per share)	$ 25
Senior Notes \| Five Point Two Five Percent Senior Notes Due April 15, 2025
Related Party Transaction [Line Items]
Aggregate principal amount issued		$ 175,000,000
Stated interest rate		5.25%
Director \| Underwriting Fees
Related Party Transaction [Line Items]
Expenses from transactions with related parties	$ 590,000	$ 263,000
Expenses from transactions with related parties, net of related expenses	$ 515,000	$ 221,000
Former Chairman \| Former Management Member
Related Party Transaction [Line Items]
Expenses from transactions with related parties				$ 200,000	$ 0
Strategic advisor agreement period				1 year
Underwritten Public Offering
Related Party Transaction [Line Items]
Depository shares issued	4,000,000
Price per share of depository shares (in usd per share)	$ 25.00
Underwritten Public Offering \| Series D Preferred Stock
Related Party Transaction [Line Items]
Depository shares to preferred stock ratio	2.50%
Non cumulative preferred stock, dividend rate	7.375%
Liquidation preference value	$ 1,000
Over Allotment Option
Related Party Transaction [Line Items]
Depository shares issued	600,000
Over Allotment Option \| Series D Preferred Stock
Related Party Transaction [Line Items]
Underwriters option period	30 days
Common Stock
Related Party Transaction [Line Items]
Issuance of stock shares			5,150,000
Underwriters option period			30 days
Common Stock \| Director \| Underwriting Fees
Related Party Transaction [Line Items]
Expenses from transactions with related parties			$ 521,000
Expenses from transactions with related parties, net of related expenses			$ 481,000
Common Stock \| Underwritten Public Offering
Related Party Transaction [Line Items]
Issuance of stock shares			5,150,000
Common Stock \| Over Allotment Option
Related Party Transaction [Line Items]
Issuance of stock shares			772,500
Underwriters option period			30 days