SUMMARY OF PRINCIPAL ACCOUNTING POLICIES - Summary of assets measured at fair value on a non-recurring basis (Detail) ¥ in Thousands, $ in Thousands	Mar. 31, 2022 CNY (¥)	Mar. 31, 2022 USD ($)	Sep. 30, 2021 CNY (¥)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Property and equipment	¥ 38,426	$ 6,062	¥ 38,940

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant