Borrowings, other debts and derivative liabilities - Summary of Maturities of Long-term Debt (Detail) - CNY (¥) ¥ in Thousands	Mar. 31, 2023	Mar. 31, 2022
Debt Disclosure [Abstract]
Within 1 year	¥ 86,261	¥ 161,126
Total	¥ 86,261	¥ 161,126

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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