Restricted net assets - Additional Information (Detail) ¥ in Thousands	12 Months Ended
Mar. 31, 2022 CNY (¥)
Restricted net assets of the Company's subsidiaries and the VIEs.	¥ 0
Threshold maximum percentage of restricted net assets of consolidated and unconsolidated subsidiaries to the consolidated net assets	25.00%
Threshold maximum percentage of restricted net assets not met by the consolidated subsidiaries to disclose the financial statements for the parent company	25.00%
PRC [Member]
Required minimum percentage of annual appropriations to general reserve fund or statutory surplus fund	10
PRC [Member] \| Statutory Surplus Reserve [Member] \| Domestic Enterprise [Member]
Required minimum percentage of annual appropriations to general reserve fund	10
Maximum percentage of statutory surplus reserve related to entity's registered capital	50

Minimum portion of after tax profit to be allocated to statutory surplus under PRC law.

No definition available.

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- Definition

Percentage of net after tax profits to be set aside prior to payment of dividends as general reserve fund or statutory surplus fund.

+ References

No definition available.

+ Details

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Data Type:	xbrli:pureItemType
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- Definition

Required statutory surplus registered capital ratio to deforce compulsory net profit allocation to statutory surplus.

+ References

No definition available.

+ Details

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Namespace Prefix:	bq_
Data Type:	xbrli:pureItemType
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- Definition

Restricted net assets of the Company's subsidiaries and the VIEs.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Threshold maximum percentage of restricted net assets not met by the consolidated subsidiaries to disclose the financial statements for the parent company.

+ References

No definition available.

+ Details

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- Definition

Threshold maximum percentage of restricted net assets of consolidated and unconsolidated subsidiaries to the consolidated net assets.

+ References

No definition available.

+ Details

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Namespace Prefix:	bq_
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Period Type:

- Details

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Namespace Prefix:
Data Type:	na
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Period Type: