Leases - Schedule of Supplemental Consolidated Balance Sheet Information Related to Leases (Detail) ¥ in Thousands, $ in Thousands	Mar. 31, 2024 CNY (¥)	Mar. 31, 2024 USD ($)	Mar. 31, 2023 CNY (¥)	Apr. 01, 2022 CNY (¥)
Leases [Abstract]
Right-of-use assets	¥ 2,576	$ 357	¥ 5,441	¥ 16,427
Current portion of lease liabilities	1,888	261	2,654
Non-current lease liabilities	¥ 773	$ 107	¥ 753

No definition available.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479041/842-20-45-1

+ Details

Name:	us-gaap_OperatingLeaseLiabilityCurrent
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

+ References

+ Details

Name:	us-gaap_OperatingLeaseLiabilityNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479041/842-20-45-1

+ Details

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Balance Type:	debit
Period Type:	instant