Change of valuation allowance.

No definition available.

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- Definition

Preferential tax rate.

+ References

No definition available.

+ Details

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.Fact.4)
-URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

+ Details

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- Definition

A description of the factual circumstances giving rise to an income tax exemption or special reduction received from a taxing jurisdiction.

+ References

No definition available.

+ Details

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319

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Income taxes - Additional Information (Detail) - CNY (¥) ¥ in Millions		12 Months Ended
	Jul. 25, 2018	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Income tax rate		25.00%	25.00%	25.00%
Income tax holiday, description	the entity could enjoy a tax holiday of 2-year CIT exemption and subsequently 3-year 12.5% preferential tax rate
Change of valuation allowance		¥ 150.0	¥ 112.5
Operating loss carry forwards		¥ 574.0	¥ 425.0
HK [Member] \| Maximum [Member]
Income tax rate		16.50%
HK [Member] \| Minimum [Member]
Income tax rate		8.25%
CHINA [Member]
Income tax rate		25.00%
Preferential tax rate		15.00%