Name:	bzun_RedeemableNonControllingEquityCarryingAmountRollforward
Namespace Prefix:	bzun_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Value of adjustment made to redeemable noncontrolling interest.

No definition available.

Name:	bzun_RedeemableNoncontrollingInterestAdjustments
Namespace Prefix:	bzun_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Amount of increase in redeemable noncontrolling interest from a business combination.

No definition available.

Name:	bzun_RedeemableNoncontrollingInterestIncreaseFromBusinessCombination
Namespace Prefix:	bzun_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Amount of redeemable noncontrolling interest reclassified to noncontrolling interest.

No definition available.

Name:	bzun_RedeemableNoncontrollingInterestReclassification
Namespace Prefix:	bzun_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The carrying amount of shares settled for derivative liability.

No definition available.

Name:	bzun_SharesSettledForDerivativeLiabilityValue
Namespace Prefix:	bzun_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(19))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

Name:	us-gaap_NetIncomeLossAttributableToRedeemableNoncontrollingInterest
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 480
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479887/480-10-S45-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 480
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479857/480-10-S50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 480
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479887/480-10-S45-3

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 480
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3A
-Subparagraph (24)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480244/480-10-S99-3A

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 480
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (01)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480244/480-10-S99-1