Adjustments at extinguishment of preferred shares.

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Issue of warrants.

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Offering Price of converted shares.

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Preferred stock liquidation preference percentage.

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Internal rate of return.

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Qualified public offering price.

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The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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-Topic 230
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Amount of addition (reduction) to the amount at which an instrument classified in shareholders' equity could be incurred (settled) in a current transaction between willing parties.

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No definition available.

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The cash outflow for cost incurred directly with the issuance of an equity security.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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- Definition

The number of nonredeemable preferred stock (shares) (or preferred stock redeemable solely at the option of the issuer) allocated to investors to buy shares of a new issue of preferred stock before they are offered to the public. When stock is sold on a subscription basis, the issuer does not initially receive the total proceeds. In general, the issuer does not issue the shares to the investor until it receives the entire proceeds.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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Amount of subscription received from investors who have been allocated nonredeemable preferred stock or preferred stock redeemable solely at the option of the issuer.

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- Definition

The cash inflow from issuance of preferred stocks identified as being convertible into another form of financial instrument, typically the entity's common stock.

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Proceeds from issuance of capital stock which provides for a specific dividend that is paid to the shareholders before any dividends to common stockholders and which takes precedence over common stockholders in the event of liquidation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The number of securities classified as temporary equity that have been issued and are held by the entity's shareholders. Securities outstanding equals securities issued minus securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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Convertible Preferred Shares - Additional Information (Detail) $ / shares in Units, ¥ in Thousands														9 Months Ended			11 Months Ended
	Jan. 17, 2020 shares	Dec. 25, 2019 USD ($) $ / shares	Nov. 06, 2019 CNY (¥) shares	Nov. 06, 2019 USD ($) shares	Oct. 17, 2019 USD ($) shares	Jul. 06, 2018 CNY (¥)	Jul. 06, 2018 USD ($) $ / shares shares	Sep. 22, 2017 CNY (¥) shares	Sep. 22, 2017 USD ($) shares	Sep. 06, 2017 CNY (¥)	Sep. 06, 2017 USD ($) $ / shares shares	Oct. 18, 2016 CNY (¥) shares	Oct. 18, 2016 USD ($) shares	Sep. 30, 2020 CNY (¥) shares	Sep. 30, 2020 USD ($) shares	Sep. 30, 2019 CNY (¥)	Dec. 25, 2019 CNY (¥)	Dec. 25, 2019 USD ($) $ / shares	Dec. 31, 2019 shares	Jul. 25, 2019 USD ($) shares	Jun. 29, 2018 shares
Temporary Equity [Line Items]
Stock Issuance Costs														¥ 27,088	$ 3,990,000	¥ 1,316
Offering Price of converted shares \| $		$ 1,000,000,000
Preferred Stock Liquidation Preference Percentage														(100.00%)	(100.00%)
Internal Rate of Return														(12.00%)	(12.00%)
Maximum [Member]
Temporary Equity [Line Items]
Final Offering Price \| $ / shares		$ 5.22																$ 5.22
Minimum [Member]
Temporary Equity [Line Items]
Final Offering Price \| $ / shares		$ 4.176																$ 4.176
Series A1 And A2 Preferred Stock [Member]
Temporary Equity [Line Items]
Consideration in issuance Preference Shares												¥ 74,742	$ 11,282,000
Issuance of Preference Shares												5,141,587	5,141,587
Convertible Preferred Stock Series A3 [Member]
Temporary Equity [Line Items]
Issuance of Warrants												2,246,744	2,246,744
Series A3 Preferred Stock [Member]
Temporary Equity [Line Items]
Preferred Stock Price \| $ / shares											$ 2.55
Consideration in issuance Preference Shares										¥ 289,024	$ 42,645,000
Issuance of Preference Shares											16,723,646
Convertible Preferred Stock Series B [Member]
Temporary Equity [Line Items]
Issuance of Warrants								5,633,780	5,633,780
Consideration in issuance Preference Shares								¥ 346,515	$ 52,546,000
Issuance of Preference Shares								15,894,594	15,894,594
Preferred stock, shares outstanding	23,288,783
Number of preferred shares converted to common shares	23,288,783
Convertible Preferred Stock Series B-2 [Member]
Temporary Equity [Line Items]
Issuance of Warrants								2,620,842	2,620,842
Number of preferred shares converted to common shares	3,571,427
Temporary Equity, Shares Outstanding	3,301,849
Convertible Preferred Stock Series A Three Upon Exercise [Member]
Temporary Equity [Line Items]
Issuance of Preference Shares																					8,361,823
Convertible Preferred Stock Series B-1 Upon Conversion [Member]
Temporary Equity [Line Items]
Issuance of Preference Shares																					2,535,201
Preferred stock, shares outstanding	3,714,580
Number of preferred shares converted to common shares	3,714,580
Convertible Preferred Stock Series B Two Upon Exercise [Member]
Temporary Equity [Line Items]
Issuance of Preference Shares							1,048,337														2,253,512
Number of preferred shares converted to common shares	3,571,427
Temporary Equity, Shares Outstanding	3,301,849
Convertible Preferred Stock Series B Upon Exercise [Member]
Temporary Equity [Line Items]
Issuance of Preference Shares							1,455,549														5,938,640
Convertible Preferred Stock Series B One Upon Exercise [Member]
Temporary Equity [Line Items]
Issuance of Preference Shares							232,161														947,218
Series C Preferred Stock [Member]
Temporary Equity [Line Items]
Preferred Stock Price \| $ / shares							$ 6.4419
Consideration in issuance Preference Shares						¥ 1,323,363	$ 200,000,000
Issuance of Preference Shares							31,046,360
Stock Issuance Costs \| ¥						¥ 16,730
Number of preferred shares converted to common shares	34,420,469
Temporary Equity, Shares Outstanding	31,046,360
Series C One Preferred Stock [Member]
Temporary Equity [Line Items]
Stock Issuance Costs			¥ 5,887	$ 840,000
Subscription of Preferred shares																				3,857,143
Aggregate Purchase Price \| $																				$ 27,000,000.0
Adjustments At Extinguishment Of Preferred Shares \| $		$ 800,000
Number of preferred shares converted to common shares	4,537,814
Series C-1 Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Consideration in issuance Preference Shares			119,387	$ 17,000,000
Consideration in issuance Preference Shares			¥ 70,036		$ 10,000,000
Issuance of Preference Shares			2,428,572	2,428,572	1,428,571
Number of preferred shares converted to common shares	4,537,814
Temporary Equity, Shares Outstanding	3,857,143
Temporary Equity [Member] \| Preferred Stock [Member]
Temporary Equity [Line Items]
Increase in the fair value of ordinary shares																	¥ 27,800	$ 4,000,000.0
Series A Convertible Preferred Shares [Member]
Temporary Equity [Line Items]
Preferred stock, shares outstanding	30,227,056
Number of preferred shares converted to common shares	30,227,056
Temporary Equity, Shares Outstanding														0	0				30,227,056
Series B Convertible Preferred Shares [Member]
Temporary Equity [Line Items]
Preferred stock, shares outstanding	23,288,783
Number of preferred shares converted to common shares	23,288,783
Temporary Equity, Shares Outstanding														0	0				30,305,212