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Loans And Leases Receivable, Commitments To Expire In Next Fiscal Year

No definition available.

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Loans And Leases Receivable, Commitments To Purchase Or Sell Expiring In Next Fiscal Year

No definition available.

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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.

No definition available.

Name:	us-gaap_FairValueOffBalanceSheetRisksDisclosureInformationLineItems
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A valuation allowance for financing receivables that are expected to be uncollectible.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

No definition available.

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Reflects the carrying amount of loans and leases for which agreements to acquire or dispose exist.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51676700&loc=d3e61044-112788

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=51676700&loc=d3e61082-112788

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Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CommitmentsToExtendCreditMember
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Data Type:	na
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Name:	us-gaap_FinancialInstrumentAxis=ewbc_CommercialAndStandbyLettersOfCreditMember
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Name:	us-gaap_FinancialInstrumentAxis=ewbc_CommercialLettersOfCreditMember
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