XML 68 R57.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Derivatives (Details) $ in Thousands | Sep. 30, 2017 USD ($) company | Dec. 31, 2016 USD ($)
--- | --- | ---
Fair Values of Derivative Instruments |  |
Derivative Assets | $ 80,466 | $ 83,780
Derivative Liabilities | 90,915 | 82,323
Derivatives designated as hedging instruments |  |
Fair Values of Derivative Instruments |  |
Notional Amount | 42,566 | 131,391
Derivative Assets | 0 | 4,325
Derivative Liabilities | 6,648 | 5,976
Derivatives designated as hedging instruments | Interest rate swaps on certificates of deposit |  |
Fair Values of Derivative Instruments |  |
Notional Amount | 42,566 | 48,365
Derivative Assets | 0 | 0
Derivative Liabilities | 6,648 | 5,976
Derivatives designated as hedging instruments | Foreign currency forward contracts |  |
Fair Values of Derivative Instruments |  |
Notional Amount | 0 | 83,026
Derivative Assets | 0 | 4,325
Derivative Liabilities | 0 | 0
Derivatives not designated as hedging instruments |  |
Fair Values of Derivative Instruments |  |
Notional Amount | 9,942,781 | 8,507,660
Derivative Assets | 80,466 | 79,455
Derivative Liabilities | 84,267 | 76,347
Derivatives not designated as hedging instruments | Interest rate swaps and options |  |
Fair Values of Derivative Instruments |  |
Notional Amount | 8,742,980 | 7,668,482
Derivative Assets | 64,822 | 67,578
Derivative Liabilities | 64,212 | 65,131
Derivatives not designated as hedging instruments | Foreign exchange contracts |  |
Fair Values of Derivative Instruments |  |
Notional Amount | 1,131,414 | 767,764
Derivative Assets | 14,187 | 11,874
Derivative Liabilities | 20,054 | 11,213
Derivatives not designated as hedging instruments | RPAs |  |
Fair Values of Derivative Instruments |  |
Notional Amount | 68,387 | 71,414
Derivative Assets | 2 | 3
Derivative Liabilities | 1 | 3
Derivatives not designated as hedging instruments | Warrants |  |
Fair Values of Derivative Instruments |  |
Notional Amount | 0 | 0
Derivative Assets | 1,455 | 0
Derivative Liabilities | 0 | $ 0
Derivatives not designated as hedging instruments | Warrant, Public Companies |  |
Fair Values of Derivative Instruments |  |
Derivative Assets | $ 856 |
Number of companies in which warrants are held | company | 4 |
Derivatives not designated as hedging instruments | Warrant, Private Companies |  |
Fair Values of Derivative Instruments |  |
Derivative Assets | $ 599 |
Number of companies in which warrants are held | company | 32 |

X
- Definition Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
Name: | invest_DerivativeNonmonetaryNotionalAmount
Namespace Prefix: | invest_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
Name: | invest_DerivativeNotionalAmount
Namespace Prefix: | invest_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Definition Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
Name: | us-gaap_DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and elected not to be offset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
Name: | us-gaap_DerivativeLiabilityFairValueGrossLiabilityIncludingNotSubjectToMasterNettingArrangement
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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

X
- Details
Name: | us-gaap_HedgingDesignationAxis=us-gaap_DesignatedAsHedgingInstrumentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateSwapMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_ForeignExchangeForwardMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_HedgingDesignationAxis=us-gaap_NondesignatedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_ForeignExchangeContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_CreditRiskContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_WarrantMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=ewbc_WarrantPublicCompaniesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=ewbc_WarrantPrivateCompaniesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |