Fair value measurements - Summary of Company's Financial Assets and Liabilities (Detail) - CNY (¥) ¥ in Thousands	Mar. 31, 2023	Mar. 31, 2022
Assets:
Available-for-sale debt investments	¥ 68,011	¥ 74,866
Equity securities with readily determinable fair values	102	670
Fair Value, Recurring [Member]
Assets:
Short-term investments	69,797	128,084
Available-for-sale debt investments	68,011	74,866
Equity securities with readily determinable fair values	102	670
Total assets	137,910	203,620
Liabilities:
Derivative liabilities	10,701	9,086
Fair Value, Recurring [Member] \| Significant unobservable Inputs (Level 1) [Member]
Assets:
Equity securities with readily determinable fair values	102	670
Total assets	102	670
Fair Value, Recurring [Member] \| Significant other observable Inputs (Level 2) [Member]
Assets:
Short-term investments	69,797	128,084
Total assets	69,797	128,084
Fair Value, Recurring [Member] \| Significant unobservable Inputs (Level 3) [Member]
Assets:
Available-for-sale debt investments	68,011	74,866
Total assets	68,011	74,866
Liabilities:
Derivative liabilities	¥ 10,701	¥ 9,086

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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Amount of short-term investments classified as other.

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