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v2.3.0.11

COVERED ASSETS AND FDIC INDEMNIFICATION ASSET, Covered Assets and Credit Quality Indicators (Details) (USD $) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2011 | Jun. 30, 2010 | Jun. 30, 2011 | Jun. 30, 2010 | Dec. 31, 2010
Business Acquisition [Line Items] |  |  |  |  |  |  |  |
Term of commercial loan shared-loss agreement (in years) | 5Y |  |  | 5Y |  |  |  |
Term of single-family residential mortgage loan shared-loss agreement (in years) | 10Y |  |  | 10Y |  |  |  |
Term of loss recovery provisions for commercial loans (in years) | 8Y |  |  | 8Y |  |  |  |
Term of loss recovery provisions for single-family residential mortgage loans (in years) | 10Y |  |  | 10Y |  |  |  |
Number of days following the 10th anniversary of the acquisition date upon which the Company will be required to pay a calculated amount to the FDIC (in days) | 45D |  |  | 45D |  |  |  |
Percentage of excess resulting from the calculation of liability to the FDIC (in hundredths) | 50.00% |  |  | 50.00% |  |  |  |
Percentage of the Intrinsic Loss Estimate used in the calculation of the liability to the FDIC (in hundredths) | 20.00% |  |  | 20.00% |  |  |  |
Percentage of the asset discount used in the calculation of the liability to the FDIC (in hundredths) | 25.00% |  |  | 25.00% |  |  |  |
Percentage of the Cumulative Shared-Loss Payments used in the calculation of the liability to the FDIC (in hundredths) | 25.00% |  |  | 25.00% |  |  |  |
Estimated liability for WFIB and UCB that will be due to the FDIC based on specific thresholds of losses not being reached | $ 7,000,000 |  |  | $ 7,000,000 |  |  |  |
Credit Quality Indicators [Abstract] |  |  |  |  |  |  |  |
Additional advances under shared-loss agreements | 607,500,000 |  |  | 607,500,000 |  |  |  |
Total allowance allocated to additional advances | 6,700,000 |  |  | 6,700,000 |  |  |  |
Percentage of allowance allocated to additional advances | 3.10% |  |  | 3.10% |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 5,309,627,000 |  |  | 5,309,627,000 |  |  | 5,955,773,000 |
Covered discount | (946,301,000) |  |  | (946,301,000) |  |  | (1,150,672,000) |
Net valuation of loans | 4,363,301,000 |  |  | 4,363,301,000 |  |  | 4,805,101,000 |
Allowance on covered loans | (6,731,000) |  |  | (6,731,000) |  |  | (4,225,000) |
Total covered loans, net | 4,356,595,000 |  |  | 4,356,595,000 |  |  | 4,880,876,000 |
Covered Nonperforming Assets [Abstract] |  |  |  |  |  |  |  |
Covered nonaccrual loans | 242,106,000 | [1] |  | 242,106,000 | [1] |  | 379,797,000 | [1]
Covered loans past due 90 days or more but not on nonaccrual | 0 |  |  | 0 |  |  | 0 |
Total nonperforming loans | 242,106,000 |  |  | 242,106,000 |  |  | 379,797,000 |
Other real estate owned covered, net | 123,050,000 |  |  | 123,050,000 |  |  | 123,902,000 |
Total covered nonperforming assets | 365,156,000 |  |  | 365,156,000 |  |  | 503,699,000 |
Number of covered OREO properties | 98 |  |  | 98 |  |  | 114 |
Percentage of covered OREO properties located in California (in hundredths) | 61.00% |  |  | 61.00% |  |  |  |
Percentage of covered OREO properties located in Washington (in hundredths) | 32.00% |  |  | 32.00% |  |  |  |
Number of covered OREO properties added during the period |  |  |  | 70 |  |  |  |
Aggregate carrying value of covered OREO properties sold during the period |  |  |  | 79,900,000 |  |  |  |
Amount of net writedowns included in aggregate carrying value on covered OREO properties |  |  |  | 18,100,000 |  |  |  |
Number of covered OREO properties sold during the period |  |  |  | 86 |  |  |  |
Total carrying value of covered OREO properties sold during the period |  |  |  | 63,200,000 |  |  |  |
Combined net gains (losses) on covered OREO properties sold during the period |  |  |  | 633,000 |  |  |  |
Changes in the accretable yield for the covered loans [Rollforward] |  |  |  |  |  |  |  |
Balance at beginning of period | 1,068,116,000 |  | 771,549,000 | 1,153,272,000 |  | 983,107,000 |  |
Additions | 0 |  | 84,556,000 | 0 |  | 84,556,000 |  |
Accretion | (52,760,000) |  | (3,664,000) | (111,440,000) |  | (7,517,000) |  |
Cash receipts, disposals and changes in expected cash flows | (34,424,000) |  | 133,948,000 | (60,900,000) |  | (73,757,000) |  |
Balance at end of period | 980,932,000 |  | 986,389,000 | 980,932,000 |  | 986,389,000 |  |
Washington First International Bank [Member] |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |
Percentage of loans receivable acquired covered by shared-loss agreements (in hundredths) | 99.00% |  |  | 99.00% |  |  |  |
Percentage of eligible losses for which the FDIC is obligated to reimburse the Company (in hundredths) | 80.00% |  |  | 80.00% |  |  |  |
Minimum percentage obligation to reimburse the FDIC for eligible recoveries related to covered assets (in hundredths) | 80.00% |  |  | 80.00% |  |  |  |
United Commercial Bank [Member] |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |
Percentage of loans receivable acquired covered by shared-loss agreements (in hundredths) | 100.00% |  |  | 100.00% |  |  |  |
Percentage of eligible losses for which the FDIC is obligated to reimburse the Company (in hundredths) | 80.00% |  |  | 80.00% |  |  |  |
Percentage of eligible losses in excess of a specified amount for which the FDIC is obligated to reimburse the Company (in hundredths) | 95.00% |  |  | 95.00% |  |  |  |
Amount of eligible losses over which the FDIC is obligated to reimburse a higher percentage | 2,050,000,000 |  |  | 2,050,000,000 |  |  |  |
Minimum percentage obligation to reimburse the FDIC for eligible recoveries related to covered assets (in hundredths) | 80.00% |  |  | 80.00% |  |  |  |
Maximum percentage obligation to reimburse the FDIC for eligible recoveries related to covered assets (in hundredths) | 95.00% |  |  | 95.00% |  |  |  |
Commercial and Industrial [Member] |  |  |  |  |  |  |  |
Credit Quality Indicators [Abstract] |  |  |  |  |  |  |  |
Additional advances under shared-loss agreements | 400,100,000 |  |  | 400,100,000 |  |  |  |
Total allowance allocated to additional advances | 2,700,000 |  |  | 2,700,000 |  |  |  |
Commercial Real Estate [Member] |  |  |  |  |  |  |  |
Credit Quality Indicators [Abstract] |  |  |  |  |  |  |  |
Additional advances under shared-loss agreements | 167,200,000 |  |  | 167,200,000 |  |  |  |
Total allowance allocated to additional advances | 3,800,000 |  |  | 3,800,000 |  |  |  |
Consumer [Member] |  |  |  |  |  |  |  |
Credit Quality Indicators [Abstract] |  |  |  |  |  |  |  |
Additional advances under shared-loss agreements | 28,700,000 |  |  | 28,700,000 |  |  |  |
Total allowance allocated to additional advances | 168,000 |  |  | 168,000 |  |  |  |
Residential [Member] |  |  |  |  |  |  |  |
Credit Quality Indicators [Abstract] |  |  |  |  |  |  |  |
Additional advances under shared-loss agreements | 11,500,000 |  |  | 11,500,000 |  |  |  |
Total allowance allocated to additional advances | 77,000 |  |  | 77,000 |  |  |  |
Real Estate Loans [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 4,256,098,000 |  |  | 4,256,098,000 |  |  | 4,776,263,000 |
Real Estate Loans [Member] | Residential Single-family [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 497,846,000 |  |  | 497,846,000 |  |  | 553,541,000 |
Real Estate Loans [Member] | Residential Single-family [Member] | Pass/Watch [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 469,239,000 |  |  | 469,239,000 |  |  | 525,979,000 |
Real Estate Loans [Member] | Residential Single-family [Member] | Special Mention [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 1,387,000 |  |  | 1,387,000 |  |  | 2,153,000 |
Real Estate Loans [Member] | Residential Single-family [Member] | Substandard [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 27,220,000 |  |  | 27,220,000 |  |  | 25,157,000 |
Real Estate Loans [Member] | Residential Single-family [Member] | Doubtful [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 0 |  |  | 0 |  |  | 252,000 |
Real Estate Loans [Member] | Residential Multifamily [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 1,008,114,000 |  |  | 1,008,114,000 |  |  | 1,093,331,000 |
Real Estate Loans [Member] | Residential Multifamily [Member] | Pass/Watch [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 837,517,000 |  |  | 837,517,000 |  |  | 1,008,274,000 |
Real Estate Loans [Member] | Residential Multifamily [Member] | Special Mention [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 29,981,000 |  |  | 29,981,000 |  |  | 15,114,000 |
Real Estate Loans [Member] | Residential Multifamily [Member] | Substandard [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 140,616,000 |  |  | 140,616,000 |  |  | 67,366,000 |
Real Estate Loans [Member] | Residential Multifamily [Member] | Doubtful [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 0 |  |  | 0 |  |  | 2,577,000 |
Real Estate Loans [Member] | Commercial and Industrial Real Estate [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 1,958,440,000 |  |  | 1,958,440,000 |  |  | 2,085,674,000 |
Real Estate Loans [Member] | Commercial and Industrial Real Estate [Member] | Pass/Watch [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 1,376,656,000 |  |  | 1,376,656,000 |  |  | 1,520,135,000 |
Real Estate Loans [Member] | Commercial and Industrial Real Estate [Member] | Special Mention [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 54,765,000 |  |  | 54,765,000 |  |  | 89,870,000 |
Real Estate Loans [Member] | Commercial and Industrial Real Estate [Member] | Substandard [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 518,267,000 |  |  | 518,267,000 |  |  | 466,588,000 |
Real Estate Loans [Member] | Commercial and Industrial Real Estate [Member] | Doubtful [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 8,752,000 |  |  | 8,752,000 |  |  | 9,081,000 |
Real Estate Loans [Member] | Construction and Land [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 791,698,000 |  |  | 791,698,000 |  |  | 1,043,717,000 |
Real Estate Loans [Member] | Construction and Land [Member] | Pass/Watch [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 252,088,000 |  |  | 252,088,000 |  |  | 328,214,000 |
Real Estate Loans [Member] | Construction and Land [Member] | Special Mention [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 67,798,000 |  |  | 67,798,000 |  |  | 125,688,000 |
Real Estate Loans [Member] | Construction and Land [Member] | Substandard [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 462,774,000 |  |  | 462,774,000 |  |  | 556,070,000 |
Real Estate Loans [Member] | Construction and Land [Member] | Doubtful [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 9,038,000 |  |  | 9,038,000 |  |  | 33,745,000 |
Real Estate Loans [Member] | Pass/Watch [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 2,935,500,000 |  |  | 2,935,500,000 |  |  | 3,382,602,000 |
Real Estate Loans [Member] | Special Mention [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 153,931,000 |  |  | 153,931,000 |  |  | 232,825,000 |
Real Estate Loans [Member] | Substandard [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 1,148,877,000 |  |  | 1,148,877,000 |  |  | 1,115,181,000 |
Real Estate Loans [Member] | Doubtful [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 17,790,000 |  |  | 17,790,000 |  |  | 45,655,000 |
Other Loans [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 1,053,529,000 |  |  | 1,053,529,000 |  |  | 1,179,510,000 |
Other Loans [Member] | Commercial Business [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 949,368,000 |  |  | 949,368,000 |  |  | 1,072,020,000 |
Other Loans [Member] | Commercial Business [Member] | Pass/Watch [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 727,980,000 |  |  | 727,980,000 |  |  | 834,252,000 |
Other Loans [Member] | Commercial Business [Member] | Special Mention [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 65,216,000 |  |  | 65,216,000 |  |  | 64,702,000 |
Other Loans [Member] | Commercial Business [Member] | Substandard [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 147,463,000 |  |  | 147,463,000 |  |  | 161,401,000 |
Other Loans [Member] | Commercial Business [Member] | Doubtful [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 8,709,000 |  |  | 8,709,000 |  |  | 11,665,000 |
Other Loans [Member] | Other Consumer [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 104,161,000 |  |  | 104,161,000 |  |  | 107,490,000 |
Other Loans [Member] | Other Consumer [Member] | Pass/Watch [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 102,713,000 |  |  | 102,713,000 |  |  | 106,232,000 |
Other Loans [Member] | Other Consumer [Member] | Special Mention [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 218,000 |  |  | 218,000 |  |  | 336,000 |
Other Loans [Member] | Other Consumer [Member] | Substandard [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 1,230,000 |  |  | 1,230,000 |  |  | 922,000 |
Other Loans [Member] | Other Consumer [Member] | Doubtful [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 0 |  |  | 0 |  |  | 0 |
Other Loans [Member] | Pass/Watch [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 830,693,000 |  |  | 830,693,000 |  |  | 940,484,000 |
Other Loans [Member] | Special Mention [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 65,434,000 |  |  | 65,434,000 |  |  | 65,038,000 |
Other Loans [Member] | Substandard [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 148,693,000 |  |  | 148,693,000 |  |  | 162,323,000 |
Other Loans [Member] | Doubtful [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 8,709,000 |  |  | 8,709,000 |  |  | 11,665,000 |
Pass/Watch [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 3,766,193,000 |  |  | 3,766,193,000 |  |  | 4,323,086,000 |
Special Mention [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 219,365,000 |  |  | 219,365,000 |  |  | 297,863,000 |
Substandard [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | 1,297,570,000 |  |  | 1,297,570,000 |  |  | 1,277,504,000 |
Doubtful [Member] |  |  |  |  |  |  |  |
Carrying Amounts And Composition Of Covered Loans [Line Items] |  |  |  |  |  |  |  |
Total principal balance | $ 26,499,000 |  |  | $ 26,499,000 |  |  | $ 57,320,000 |
[1] | Covered nonaccrual loans meet the criteria for nonaccrual but have a yield accreted through interest income under ASC 310-30.

X
- Definition Additional advances on covered loans included in covered loans under the shared-loss agreements but not accounted for under ASU 310-30. + Details
Name: | ewbc_AdditionalAdvancesUnderSharedLossAgreements
Namespace Prefix: | ewbc
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Aggregate carrying value of OREO properties covered by shared-loss agreements that were added during the period. + Details
Name: | ewbc_AggregateCarryingValueOfCoveredOreoPropertiesAdded
Namespace Prefix: | ewbc
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The allowance for loan losses represents the reserve to cover probable credit losses related to specifically identified loans (loans covered by shared loss agreements), as of the balance sheet date. + Details
Name: | ewbc_AllowanceForLoanLossesCoveredLoans
Namespace Prefix: | ewbc
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of eligible losses for covered assets over which the FDIC is obligated to reimburse a higher percentage pursuant to the shared-loss agreements. + Details
Name: | ewbc_AmountOfEligibleLossesOverWhichFdicIsObligatedToReimburseHigherPercentage
Namespace Prefix: | ewbc
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount of net writedowns during the period included in the aggregate carrying value of OREO properties covered by shared-loss agreements. + Details
Name: | ewbc_AmountOfNetWritedownsIncludedInAggregateCarryingValue
Namespace Prefix: | ewbc
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- 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. + Details
Name: | ewbc_CarryingAmountsAndCompositionOfCoveredLoansLineItems
Namespace Prefix: | ewbc
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Change in the estimate of cash flows expected to be collected due to cash receipts, disposals and changes in expected cash flows. This relates to a loan accounted for as an available-for-sale debt security, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + Details
Name: | ewbc_CashReceiptsDisposalsAndChangesInExpectedCashFlows
Namespace Prefix: | ewbc
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The combined net gains (losses) resulting from sales of OREO properties covered by shared-loss agreements during the period. + Details
Name: | ewbc_CombinedNetGainsLossesOnCoveredOreoPropertiesSold
Namespace Prefix: | ewbc
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The discount amount related to covered loans receivable as of the balance sheet date. + Details
Name: | ewbc_CoveredDiscount
Namespace Prefix: | ewbc
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The carrying amount as of the balance sheet date of covered loans receivable that are considered to be nonperforming assets and are past due 90 days or more, but are not on nonaccrual status. + Details
Name: | ewbc_CoveredLoansPastDue90DaysOrMoreButNotOnNonaccrual
Namespace Prefix: | ewbc
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The carrying amount as of the balance sheet date of covered loans receivable that are considered to be nonperforming assets and on nonaccrual status. + Details
Name: | ewbc_CoveredNonaccrualLoans
Namespace Prefix: | ewbc
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Balance Type: | debit
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- Details
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- Details
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- Definition The estimated liability that will be due to the FDIC forty-five days after the tenth anniversary of the acquisition of Washington First International Band (WFIB) and United Commercial Bank (UCB). This liability is based on specific thresholds of losses not being reached. + Details
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- Definition For an unclassified balance sheet, an amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date, before any write-downs taken for collection uncertainty on the part of the holder, for loans covered under shared loss agreements. + Details
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- Definition For an unclassified balance sheet, an amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date, net of any write-downs taken for collection uncertainty on the part of the holder, for loans covered under shared loss agreements. + Details
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Balance Type: | debit
Period Type: | instant

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- Definition Maximum percentage obligation to reimburse the FDIC for eligible recoveries related to covered assets pursuant to the shared-loss agreements. + Details
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Balance Type: | na
Period Type: | instant

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- Definition Minimum percentage obligation to reimburse the FDIC for eligible recoveries related to covered assets pursuant to the shared-loss agreements. + Details
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Balance Type: | na
Period Type: | instant

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- Definition The carrying amount as of the balance sheet date of covered loans receivable, net of discounts. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Definition The number of OREO properties as of the balance sheet date covered by shared-loss agreements. + Details
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Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

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- Definition The number of OREO properties covered by shared-loss agreements that were added during the period. + Details
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Balance Type: | na
Period Type: | duration

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- Definition The number of OREO properties covered by shared-loss agreements that were sold during the period. + Details
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Balance Type: | na
Period Type: | duration

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- Definition The number of days following the 10th anniversary of the respective acquisition date upon which the Company will be required to pay to the FDIC a calculated amount, based on the specific thresholds of losses not being reached. + Details
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Balance Type: | na
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- Definition Net real estate and foreclosed assets "covered" and guaranteed for 80% reimbursement by the FDIC's loss share agreements. + Details
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- Definition Percentage of allowance allocated to additional advances included in covered loans shared-loss agreements over the total amount of allowance on covered loans. Allowance on covered loans represents the reserve to cover probable credit losses related to specifically identified loans (loans covered by shared loss agreements), as of the balance sheet date. + Details
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Balance Type: | na
Period Type: | instant

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- Definition The percentage of the asset discount, as defined in the shared-loss agreements, used in the calculation of this liability to the FDIC. + Details
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Balance Type: | na
Period Type: | instant

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- Definition The percentage of OREO properties covered by shared-loss agreements that are located in California as of the balance sheet date. + Details
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Balance Type: | na
Period Type: | instant

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- Definition The percentage of OREO properties covered by shared-loss agreements that are located in Washington as of the balance sheet date. + Details
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Balance Type: | na
Period Type: | instant

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- Definition The percentage of the Cumulative Shared-Loss Payments, as defined in the shared-loss agreements, used in the calculation of this liability to the FDIC. + Details
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Balance Type: | na
Period Type: | instant

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- Definition Percentage of eligible losses for which the FDIC is obligated to reimburse the Company pursuant to the shared-loss agreements. + Details
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Balance Type: | na
Period Type: | instant

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- Definition Percentage of eligible losses for covered assets in excess of a certain amount for which the FDIC is obligated to reimburse the Company pursuant to the shared-loss agreements. + Details
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Period Type: | instant

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- Definition The percentage of excess resulting from the calculation of this liability to the FDIC as stated in the shared-loss agreements. + Details
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Balance Type: | na
Period Type: | instant

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- Definition The percentage of the Intrinsic Loss Estimate, as defined in the shared-loss agreements, used in the calculation of this liability to the FDIC. + Details
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Balance Type: | na
Period Type: | instant

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- Definition Percentage of loans receivable acquired covered by shared-loss agreements with the FDIC. + Details
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Balance Type: | na
Period Type: | instant

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- Definition Term of commercial loan shared-loss agreement from the acquisition date. + Details
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Balance Type: | na
Period Type: | instant

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- Definition Term of loss recovery provisions from the acquisition date for commercial loans pursuant to the shared-loss agreements. + Details
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Balance Type: | na
Period Type: | instant

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- Definition Term of loss recovery provisions from the acquisition date for single-family residential mortgage loans pursuant to the share-loss agreements. + Details
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- Definition Term of single-family residential mortgage loan shared-loss agreement from the acquisition date. + Details
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- Definition The total carrying value of OREO properties covered by shared-loss agreements that were sold during the period. + Details
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Namespace Prefix: | ewbc
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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- Definition The carrying amount as of the balance sheet date of all covered nonperforming assets. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Definition The carrying amount as of the balance sheet date of all covered loans receivable that are considered to be nonperforming assets. + Details
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Period Type: | instant

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- Definition Total amount of allowance allocated to additional advances included in covered loans shared-loss agreements. Allowance on covered loans represents the reserve to cover probable credit losses related to specifically identified loans (loans covered by shared loss agreements), as of the balance sheet date. + Details
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Balance Type: | credit
Period Type: | instant

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- 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. + Details
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- Definition The aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 03-3 -Paragraph 16 -Subparagraph a(2) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6891207&loc=d3e13503-111538 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544 + Details
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- Definition The current period recognition due to accretion of the excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 03-3 -Paragraph 16 -Subparagraph a(2) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6891207&loc=d3e13503-111538 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544 + Details
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- Definition The increases in the aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable, due to the acquisition of similar loans not accounted for as debt securities during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 03-3 -Paragraph 16 -Subparagraph a(2) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6891207&loc=d3e13503-111538 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + Details
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