COMMITMENTS AND CONTINGENCIES (Details 2) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
F&F, LLC and 618 Investment, Inc. v. East West Bank \| East West Bank
Litigation
Litigation accrual	$ 34,400	$ 31,600
Loans Sold or Securitized with Recourse
Guarantees
Principal amount of loans sold or securitized	206,500	249,800
Recourse reserve	567	2,200
Loans Sold or Securitized with Full Recourse \| Residential \| Single-family
Guarantees
Principal amount of loans sold or securitized	31,300	35,500
Loans Sold or Securitized with Limited Recourse \| Residential \| Multifamily
Guarantees
Principal amount of loans sold or securitized	$ 175,200	$ 214,300
Recourse provision limitation, maximum percentage of the top loss on the multifamily loans	4.00%

Represents the maximum percentage of the top loss on the multifamily loans with limited recourse.

No definition available.

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- Definition

This is the principal amount outstanding for sold or securitized loans only (across all types of loans).

+ References

No definition available.

+ Details

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Namespace Prefix:	ewbc_
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- References

No definition available.

+ Details

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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- References

No definition available.

+ Details

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- Definition

Amount of loss contingency liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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