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Summary of Significant Accounting Policies - Additional Information (Detail) ¥ in Thousands | 9 Months Ended
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Sep. 30, 2020 CNY (¥) | Sep. 30, 2019 CNY (¥)
Statutory Reserves [Line Items] |  |
Exchange rate | 6.7896 |
Revenue recognized that was included in the deferred revenue balance at the beginning of the year | ¥ 426,470 | ¥ 163,280
The aggregate amount of transaction price allocated to unsatisfied performance obligations | ¥ 1,045,300 |

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- Definition Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130549-203045 + Details
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