Regulatory Requirements and Matters - Narrative (Details)	Dec. 31, 2023
Capital adequacy
Common equity tier 1 capital adequacy to risk weighted assets	0.045
Banking regulation, tier one risk-based capital ratio, capital a, minimum	0.060
Banking regulation,total risk-based capital ratio, capital adequacy, minimum	0.080
Banking regulation, tier one leverage capital ratio, capital adequacy, minimum	0.040
Fully phased-in capital conservation buffer	2.50%
East West Bank
Capital adequacy
Common equity tier 1 capital adequacy to risk weighted assets	0.045
Banking regulation, tier one risk-based capital ratio, capital a, minimum	0.060
Banking regulation,total risk-based capital ratio, capital adequacy, minimum	0.080
Banking regulation, tier one leverage capital ratio, capital adequacy, minimum	0.040

Regulatory Capital, Fully Phased-in Capital Conservation Buffer

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Ratio of minimum Common Equity Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
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Ratio of minimum total risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 505
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Ratio of minimum Tier 1 leverage capital to average assets required for capital adequacy as defined by regulatory framework.

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Ratio of minimum Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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