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Convertible Preferred Shares - Additional Information (Detail) $ / shares in Units, ¥ in Thousands |  |  |  |  |  |  |  |  | 9 Months Ended | 11 Months Ended |  |  |
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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 |  |

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- Definition Adjustments at extinguishment of preferred shares. + References No definition available. + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4313-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4304-108586 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4332-108586 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(27)(b)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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