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The amount of consideration payable for share repurchase as at the end of the reporting period.

No definition available.

Name:	bz_ConsiderationPayableForShareRepurchase
Namespace Prefix:	bz_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of expenses incurred but not yet paid nor invoiced, and liabilities classified as other.

No definition available.

Name:	us-gaap_AccruedLiabilitiesAndOtherLiabilities
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Data Type:	xbrli:monetaryItemType
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- References

No definition available.

Name:	us-gaap_AccruedLiabilitiesAndOtherLiabilitiesAbstract
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The current portion, due within one year or one operating cycle, if longer, of deposits held other than customer deposits.

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Data Type:	xbrli:monetaryItemType
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Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481372/852-10-55-10

Name:	us-gaap_OtherLiabilitiesCurrent
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Data Type:	xbrli:monetaryItemType
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Carrying value as of the balance sheet date of obligations incurred and payable for statutory income, sales, use, payroll, excise, real, property and other taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
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-Topic 210
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