XML 129 R75.htm IDEA: XBRL DOCUMENT
v3.19.3

Loans Receivable and Allowance for Credit Losses (Composition of Non-PCI and PCI Loans - Narrative) (Details) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2019 USD ($) property_unit | Dec. 31, 2018 USD ($)
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES |  |
Loans receivable pledged to secure borrowings and to provide additional borrowing capacity from the FHLB and the Federal Reserve Bank | $ | $ 21,825,918 | $ 20,590,035
Consumer lending | Single-family residential and home equity line of credit |  |
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES |  |
Loan-to-value ratio (or less at origination) | 60.00% |
Multifamily residential | Commercial lending | Minimum |  |
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES |  |
Number of units in multifamily properties used to secure multifamily residential loans | property_unit | 5 |

X
- Definition Ratio which compares the amount of the borrower’s first mortgage with the appraised value of the property. It is computed as Current Loan Balance ÷ Current Appraised Value + References No definition available. + Details
Name: | ewbc_LoantoValueRatio
Namespace Prefix: | ewbc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of Units in the Multifamily Properties Used as Collateral + References No definition available. + Details
Name: | ewbc_NumberofUnitsintheMultifamilyPropertiesUsedasCollateral
Namespace Prefix: | ewbc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- 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_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5086-111524 + Details
Name: | us-gaap_LoansPledgedAsCollateral
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=ewbc_SinglefamilyResidentialandHomeEquityLineofCreditMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=srt_MultifamilyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |