XML 32 R58.htm IDEA: XBRL DOCUMENT
v3.19.3

Securities (Continuous Unrealized Losses) (Details) - USD ($) $ in Thousands | Sep. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | $ 785,217 | $ 163,128
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (2,290) | (1,518)
Available-for-sale debt securities, 12 Months or More, Fair Value | 524,008 | 2,087,534
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (5,779) | (69,249)
Available-for-sale debt securities Fair Value, Total | 1,309,225 | 2,250,662
Available-for-sale debt securities, Gross Unrealized Loss, Total | (8,069) | (70,767)
U.S. Treasury securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 199,711 | 0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (76) | 0
Available-for-sale debt securities, 12 Months or More, Fair Value | 226,402 | 516,520
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (1,346) | (12,899)
Available-for-sale debt securities Fair Value, Total | 426,113 | 516,520
Available-for-sale debt securities, Gross Unrealized Loss, Total | (1,422) | (12,899)
U.S. government agency and U.S. government sponsored enterprise debt securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 354,916 | 22,755
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (85) | (238)
Available-for-sale debt securities, 12 Months or More, Fair Value | 0 | 159,814
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | 0 | (2,456)
Available-for-sale debt securities Fair Value, Total | 354,916 | 182,569
Available-for-sale debt securities, Gross Unrealized Loss, Total | (85) | (2,694)
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 60,336 | 26,886
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (573) | (245)
Available-for-sale debt securities, 12 Months or More, Fair Value | 116,139 | 274,666
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (2,091) | (12,449)
Available-for-sale debt securities Fair Value, Total | 176,475 | 301,552
Available-for-sale debt securities, Gross Unrealized Loss, Total | (2,664) | (12,694)
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 87,356 | 75,675
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (553) | (491)
Available-for-sale debt securities, 12 Months or More, Fair Value | 43,403 | 653,660
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (353) | (14,061)
Available-for-sale debt securities Fair Value, Total | 130,759 | 729,335
Available-for-sale debt securities, Gross Unrealized Loss, Total | (906) | (14,552)
Municipal securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 979 | 9,458
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (1) | (104)
Available-for-sale debt securities, 12 Months or More, Fair Value | 5,046 | 30,295
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (6) | (928)
Available-for-sale debt securities Fair Value, Total | 6,025 | 39,753
Available-for-sale debt securities, Gross Unrealized Loss, Total | (7) | (1,032)
Non-agency commercial mortgage-backed securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 7,914 |
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (6) |
Available-for-sale debt securities, 12 Months or More, Fair Value | 0 |
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | 0 |
Available-for-sale debt securities Fair Value, Total | 7,914 |
Available-for-sale debt securities, Gross Unrealized Loss, Total | (6) |
Non-agency residential mortgage-backed securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 11,145 | 3,067
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (139) | (19)
Available-for-sale debt securities, 12 Months or More, Fair Value | 0 | 3,949
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | 0 | (166)
Available-for-sale debt securities Fair Value, Total | 11,145 | 7,016
Available-for-sale debt securities, Gross Unrealized Loss, Total | (139) | (185)
Corporate debt securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 1,247 | 10,869
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (3) | (381)
Available-for-sale debt securities, 12 Months or More, Fair Value | 9,775 | 0
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (225) | 0
Available-for-sale debt securities Fair Value, Total | 11,022 | 10,869
Available-for-sale debt securities, Gross Unrealized Loss, Total | (228) | (381)
Foreign bonds |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 14,338 | 14,418
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (101) | (40)
Available-for-sale debt securities, 12 Months or More, Fair Value | 123,243 | 448,630
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (1,758) | (26,290)
Available-for-sale debt securities Fair Value, Total | 137,581 | 463,048
Available-for-sale debt securities, Gross Unrealized Loss, Total | (1,859) | $ (26,330)
Asset-backed securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 47,275 |
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (753) |
Available-for-sale debt securities, 12 Months or More, Fair Value | 0 |
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | 0 |
Available-for-sale debt securities Fair Value, Total | 47,275 |
Available-for-sale debt securities, Gross Unrealized Loss, Total | $ (753) |

X
- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=118955579&loc=SL82922890-210455 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27337-111563 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=118942371&loc=SL82922954-210456 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=118955579&loc=SL82922890-210455 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=118955579&loc=SL82922890-210455 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=118942371&loc=SL82922954-210456 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=118955579&loc=SL82922890-210455 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27337-111563 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position without allowance for credit loss. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=118955579&loc=SL82922888-210455 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=118942371&loc=SL82922954-210456 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=118955579&loc=SL82922888-210455 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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_ScheduleOfAvailableForSaleSecuritiesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_USTreasurySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=ewbc_CommercialMortgageBackedSecuritiesIssuedByUSGovernmentAgenciesAndGovernmentSponsoredEnterpriseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=ewbc_ResidentialMortgageBackedSecuritiesIssuedByUSGovernmentAgenciesAndGovernmentSponsoredEnterpriseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_CommercialMortgageBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_ResidentialMortgageBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=ewbc_ForeignGovernmentAndCorporateDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_AssetBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |