XML 67 R50.htm IDEA: XBRL DOCUMENT
v3.21.2

Securities (Proceeds, Gross Realized Gains and Tax Expense) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Investments, Debt and Equity Securities [Abstract] |  |  |  |
Gross realized gains | $ 632 | $ 9,640 | $ 824 | $ 11,169
Related tax expense | $ 187 | $ 2,850 | $ 244 | $ 3,302

X
- Definition Tax Expense on Sale of Available for Sale Debt Investment Securities + References No definition available. + Details
Name: | ewbc_TaxExpenseonSaleofAvailableforSaleDebtInvestmentSecurities
Namespace Prefix: | ewbc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27357-111563 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleRealizedGain
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration