XML 97 R69.htm IDEA: XBRL DOCUMENT
v3.19.3

Derivatives (Derivatives Not Designated as Hedging Instruments - Foreign Exchange Contracts) (Details) - USD ($) $ in Thousands | Sep. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Derivative [Line Items] |  |
Derivative assets - Fair value | $ 358,639 | $ 107,816
Derivative liabilities - Fair value | 263,734 | 118,305
Derivatives not designated as hedging instruments |  |
Derivative [Line Items] |  |
Notional amount | 18,988,712 | 15,222,341
Derivative assets - Fair value | 358,639 | 107,816
Derivative liabilities - Fair value | 260,499 | 111,828
Derivatives not designated as hedging instruments | Foreign exchange contracts |  |
Derivative [Line Items] |  |
Notional amount | 4,638,136 | 3,407,522
Derivative assets - Fair value | 59,512 | 21,624
Derivative liabilities - Fair value | 50,397 | 19,329
Foreign exchange contracts | Customer Counterparty | Derivatives not designated as hedging instruments | Forwards and spot |  |
Derivative [Line Items] |  |
Notional amount | 3,205,662 | 2,023,425
Derivative assets - Fair value | 46,233 | 11,719
Derivative liabilities - Fair value | 34,023 | 13,079
Foreign exchange contracts | Customer Counterparty | Derivatives not designated as hedging instruments | Swaps |  |
Derivative [Line Items] |  |
Notional amount | 10,091 | 21,108
Derivative assets - Fair value | 77 | 348
Derivative liabilities - Fair value | 217 | 243
Foreign exchange contracts | Customer Counterparty | Derivatives not designated as hedging instruments | Written options |  |
Derivative [Line Items] |  |
Notional amount | 85,379 | 537
Derivative assets - Fair value | 640 | 16
Derivative liabilities - Fair value | 0 | 0
Foreign exchange contracts | Customer Counterparty | Derivatives not designated as hedging instruments | Collars |  |
Derivative [Line Items] |  |
Notional amount | 5,344 | 83,864
Derivative assets - Fair value | 30 | 0
Derivative liabilities - Fair value | 209 | 370
Foreign exchange contracts | Customer Counterparty | Derivatives not designated as hedging instruments | Foreign exchange contracts |  |
Derivative [Line Items] |  |
Notional amount | 3,306,476 | 2,128,934
Derivative assets - Fair value | 46,980 | 12,083
Derivative liabilities - Fair value | 34,449 | 13,692
Foreign exchange contracts | Financial Counterparty | Derivatives not designated as hedging instruments | Forwards and spot |  |
Derivative [Line Items] |  |
Notional amount | 321,044 | 506,342
Derivative assets - Fair value | 2,538 | 3,407
Derivative liabilities - Fair value | 5,171 | 2,285
Foreign exchange contracts | Financial Counterparty | Derivatives not designated as hedging instruments | Swaps |  |
Derivative [Line Items] |  |
Notional amount | 760,748 | 687,845
Derivative assets - Fair value | 7,239 | 5,764
Derivative liabilities - Fair value | 7,554 | 3,336
Foreign exchange contracts | Financial Counterparty | Derivatives not designated as hedging instruments | Purchased options |  |
Derivative [Line Items] |  |
Notional amount | 85,379 | 537
Derivative assets - Fair value | 0 | 0
Derivative liabilities - Fair value | 640 | 16
Foreign exchange contracts | Financial Counterparty | Derivatives not designated as hedging instruments | Collars |  |
Derivative [Line Items] |  |
Notional amount | 164,489 | 83,864
Derivative assets - Fair value | 2,755 | 370
Derivative liabilities - Fair value | 2,583 | 0
Foreign exchange contracts | Financial Counterparty | Derivatives not designated as hedging instruments | Foreign exchange contracts |  |
Derivative [Line Items] |  |
Notional amount | 1,331,660 | 1,278,588
Derivative assets - Fair value | 12,532 | 9,541
Derivative liabilities - Fair value | $ 15,948 | $ 5,637

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://fasb.org/us-gaap/role/ref/legacyRef -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://fasb.org/us-gaap/role/ref/legacyRef -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_DerivativeLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959 + Details
Name: | us-gaap_DerivativeNotionalAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

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_ForeignExchangeContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | srt_CounterpartyNameAxis=ewbc_CustomerCounterpartyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

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

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

X
- Details
Name: | srt_CounterpartyNameAxis=ewbc_FinancialCounterpartyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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