Financing Receivable, Collateral Dependent

No definition available.

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Namespace Prefix:	ewbc_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5258-111524

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953550-111524

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

+ References

+ Details

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Period Type:	instant

- Details

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- Details

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- Details

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Loans Receivable and Allowance for Credit Losses (Impaired Loans) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2020
Commercial Lending
Impaired loans disclosures
Collateral dependent loans			$ 97,200
Consumer Lending
Impaired loans disclosures
Collateral dependent loans			$ 17,300
Non-PCI impaired loans
Impaired loans disclosures
Impaired Financing Receivable, Unpaid Principal Balance	$ 266,772
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	129,748
Impaired Financing Receivable, with Related Allowance, Recorded Investment	68,369
Impaired Financing Receivable, Recorded Investment, Total	198,117
Related Allowance	5,593
Average Recorded Investment	370,190	$ 233,180
Recognized Interest Income	4,318	2,330
Non-PCI impaired loans \| Commercial Lending
Impaired loans disclosures
Impaired Financing Receivable, Unpaid Principal Balance	226,918
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	115,116
Impaired Financing Receivable, with Related Allowance, Recorded Investment	44,699
Impaired Financing Receivable, Recorded Investment, Total	159,815
Related Allowance	3,033
Average Recorded Investment	307,472	194,194
Recognized Interest Income	3,692	1,786
Non-PCI impaired loans \| Commercial Lending \| C&I
Impaired loans disclosures
Impaired Financing Receivable, Unpaid Principal Balance	174,656
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	73,956
Impaired Financing Receivable, with Related Allowance, Recorded Investment	40,086
Impaired Financing Receivable, Recorded Investment, Total	114,042
Related Allowance	2,881
Average Recorded Investment	248,619	143,430
Recognized Interest Income	2,932	1,046
Non-PCI impaired loans \| Commercial Lending \| CRE
Impaired loans disclosures
Impaired Financing Receivable, Unpaid Principal Balance	27,601
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	20,098
Impaired Financing Receivable, with Related Allowance, Recorded Investment	1,520
Impaired Financing Receivable, Recorded Investment, Total	21,618
Related Allowance	97
Average Recorded Investment	33,046	35,049
Recognized Interest Income	464	491
Non-PCI impaired loans \| Commercial Lending \| Residential loan \| Multifamily
Impaired loans disclosures
Impaired Financing Receivable, Unpaid Principal Balance	4,965
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	1,371
Impaired Financing Receivable, with Related Allowance, Recorded Investment	3,093
Impaired Financing Receivable, Recorded Investment, Total	4,464
Related Allowance	55
Average Recorded Investment	6,116	11,742
Recognized Interest Income	228	249
Non-PCI impaired loans \| Commercial Lending \| Construction and land
Impaired loans disclosures
Impaired Financing Receivable, Unpaid Principal Balance	19,696
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	19,691
Impaired Financing Receivable, with Related Allowance, Recorded Investment	0
Impaired Financing Receivable, Recorded Investment, Total	19,691
Related Allowance	0
Average Recorded Investment	19,691	3,973
Recognized Interest Income	68	0
Non-PCI impaired loans \| Commercial Lending \| Total CRE
Impaired loans disclosures
Impaired Financing Receivable, Unpaid Principal Balance	52,262
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	41,160
Impaired Financing Receivable, with Related Allowance, Recorded Investment	4,613
Impaired Financing Receivable, Recorded Investment, Total	45,773
Related Allowance	152
Average Recorded Investment	58,853	50,764
Recognized Interest Income	760	740
Non-PCI impaired loans \| Consumer Lending
Impaired loans disclosures
Impaired Financing Receivable, Unpaid Principal Balance	39,854
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	14,632
Impaired Financing Receivable, with Related Allowance, Recorded Investment	23,670
Impaired Financing Receivable, Recorded Investment, Total	38,302
Related Allowance	2,560
Average Recorded Investment	62,718	38,986
Recognized Interest Income	626	544
Non-PCI impaired loans \| Consumer Lending \| Residential loan \| Single-family
Impaired loans disclosures
Impaired Financing Receivable, Unpaid Principal Balance	23,626
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	8,507
Impaired Financing Receivable, with Related Allowance, Recorded Investment	13,704
Impaired Financing Receivable, Recorded Investment, Total	22,211
Related Allowance	35
Average Recorded Investment	37,315	22,350
Recognized Interest Income	496	474
Non-PCI impaired loans \| Consumer Lending \| HELOCs
Impaired loans disclosures
Impaired Financing Receivable, Unpaid Principal Balance	13,711
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	6,125
Impaired Financing Receivable, with Related Allowance, Recorded Investment	7,449
Impaired Financing Receivable, Recorded Investment, Total	13,574
Related Allowance	8
Average Recorded Investment	22,851	14,134
Recognized Interest Income	130	70
Non-PCI impaired loans \| Consumer Lending \| Total residential mortgage
Impaired loans disclosures
Impaired Financing Receivable, Unpaid Principal Balance	37,337
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	14,632
Impaired Financing Receivable, with Related Allowance, Recorded Investment	21,153
Impaired Financing Receivable, Recorded Investment, Total	35,785
Related Allowance	43
Average Recorded Investment	60,166	36,484
Recognized Interest Income	626	544
Non-PCI impaired loans \| Consumer Lending \| Other consumer
Impaired loans disclosures
Impaired Financing Receivable, Unpaid Principal Balance	2,517
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	2,517
Impaired Financing Receivable, Recorded Investment, Total	2,517
Related Allowance	2,517
Average Recorded Investment	2,552	2,502
Recognized Interest Income	$ 0	$ 0