OTHER ASSETS ACQUIRED THROUGH FORECLOSURE (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
OTHER ASSETS ACQUIRED THROUGH FORECLOSURE [Abstract]
Balance, beginning of period	$ 362	$ 129	$ 137	$ 198
Additions	132	48	502	213
Proceeds from dispositions	(60)	(115)	(303)	(342)
Gains (loss) on sales, net	52	(7)	150	(14)
Balance, end of period	$ 486	$ 55	$ 486	$ 55

Refers to the dispositions from participants from other real estate owned and repossessed assets.

No definition available.

Name:	cwbc_DispositionsFromParticipantsFromOtherRealEstateOwnedAndRepossessedAssets
Namespace Prefix:	cwbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The value of other real estate and other repossessed assets transferred from loans in a noncash transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	cwbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Carrying amount as of the balance sheet date of all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance; includes real and personal property; equity interests in corporations, partnerships, and joint ventures; and beneficial interests in trusts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4437-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5162-111524

+ Details

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

- Definition

The net gain (loss) resulting from sales and other disposals of other real estate owned, increases (decreases) in the valuation allowance for foreclosed real estate, and write-downs of other real estate owned after acquisition or physical possession.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.14(d))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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

- References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration