SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)	9 Months Ended
Sep. 30, 2017 Quarter Payment
Loans Held for Investment and Interest and Fees from Loans [Abstract]
Period of delinquency after which a loan is placed in a nonaccrual status	90 days
Allowance for Loan Losses and Provision for Loan Losses [Abstract]
Period of loss history used for determining the amount of allowance of loan losses \| Quarter	12
Minimum [Member]
Loans Held for Investment and Interest and Fees from Loans [Abstract]
Period of delinquency after which a loan is placed in a nonaccrual status	90 days
Other Personal Loans [Member] \| Maximum [Member]
Loans Held for Investment and Interest and Fees from Loans [Abstract]
Threshold period past due for write-off of loans	120 days
Consumer [Member]
Allowance for Loan Losses and Provision for Loan Losses [Abstract]
Period past due for unsecured loans to be charged off	120 days
Number of delinquent payments for unsecured loans to be charged off \| Payment	5
Commercial [Member]
Allowance for Loan Losses and Provision for Loan Losses [Abstract]
Period past due for unsecured loans to be charged off	90 days
Commercial Real Estate [Member]
Allowance for Loan Losses and Provision for Loan Losses [Abstract]
Period past due for unsecured loans to be charged off	90 days
SBA [Member]
Allowance for Loan Losses and Provision for Loan Losses [Abstract]
Period past due for unsecured loans to be charged off	90 days
Single Family Real Estate [Member]
Allowance for Loan Losses and Provision for Loan Losses [Abstract]
Period past due after which loans are evaluated for impairment	90 days
Single Family Real Estate [Member] \| Minimum [Member]
Allowance for Loan Losses and Provision for Loan Losses [Abstract]
Period past due for unsecured loans to be charged off	90 days
Single Family Real Estate [Member] \| Maximum [Member]
Allowance for Loan Losses and Provision for Loan Losses [Abstract]
Period past due for unsecured loans to be charged off	120 days
HELOC [Member]
Allowance for Loan Losses and Provision for Loan Losses [Abstract]
Period past due after which loans are evaluated for impairment	90 days
HELOC [Member] \| Minimum [Member]
Allowance for Loan Losses and Provision for Loan Losses [Abstract]
Period past due for unsecured loans to be charged off	90 days
HELOC [Member] \| Maximum [Member]
Allowance for Loan Losses and Provision for Loan Losses [Abstract]
Period past due for unsecured loans to be charged off	120 days
Manufactured Housing [Member]
Allowance for Loan Losses and Provision for Loan Losses [Abstract]
Period past due after which loans are evaluated for impairment	90 days
Manufactured Housing [Member] \| Minimum [Member]
Allowance for Loan Losses and Provision for Loan Losses [Abstract]
Period past due for unsecured loans to be charged off	90 days
Manufactured Housing [Member] \| Maximum [Member]
Allowance for Loan Losses and Provision for Loan Losses [Abstract]
Period past due for unsecured loans to be charged off	120 days

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Refers to the number of delinquent payments after which loan is considered as uncollectible.

+ References

No definition available.

+ Details

Name:	cwbc_NumberOfDelinquentPaymentsForUnsecuredLoansToBeChargedOff
Namespace Prefix:	cwbc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

This line item represents the period of delinquency after which a loan is placed in a nonaccrual status and ceases recognizing interest income, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	cwbc_PeriodOfDelinquencyAfterWhichALoanIsPlacedInNonaccrualStatus
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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Refers to period of loss history used for migration analysis and historical loss rate calculations for determining the amount of allowance of loan losses.

+ References

No definition available.

+ Details

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Namespace Prefix:	cwbc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Refers to period past due either of principal or interest, after which loans are evaluated for impairment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	cwbc_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Refers to period past due for unsecured loans to be charged off, in the event there is no perceived equity, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	cwbc_PeriodPastDueForUnsecuredLoansToBeChargedOff
Namespace Prefix:	cwbc_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Threshold period past due for financing receivable to write off as uncollectible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ 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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- Details

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- Details

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- Details

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