XML 33 R32.htm IDEA: XBRL DOCUMENT
v2.3.0.15

BASIS OF PRESENTATION (Details) | Sep. 30, 2011
--- | ---
BASIS OF PRESENTATION [Abstract] |
Number of wholly-owned subsidiaries that are statutory business trusts and are not consolidated | 8

X
- Definition The number of wholly-owned subsidiaries that are statutory business trusts and are not consolidated. + Details
Name: | ewbc_NumberOfWhollyOwnedSubsidiaries
Namespace Prefix: | ewbc
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract
Namespace Prefix: | us-gaap
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration