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Principal Activities and Organization - Additional Information (Detail) $ / shares in Units, ¥ in Thousands, $ in Thousands |  |  | 9 Months Ended |  |
--- | --- | --- | --- | --- | ---
Feb. 10, 2020 USD ($) $ / shares shares | Jan. 31, 2020 USD ($) shares | Jan. 31, 2020 USD ($) shares | Sep. 30, 2020 CNY (¥) | Sep. 30, 2020 USD ($) | Jan. 17, 2020 $ / shares | Oct. 31, 2016 $ / shares
Proceeds from initial public offering |  |  |  | ¥ 726,300 | $ 106,972 |  |
Share price | $ / shares |  |  |  |  |  |  | $ 0.77
IPO [Member] | American Depositary Shares [Member] |  |  |  |  |  |  |
Number of share issued, ADS | shares |  | 7,407,400 | 7,407,400 |  |  |  |
Number of share issued, price per share | $ / shares |  |  |  |  |  | $ 14.00 |
Proceeds from initial public offering | $ |  | $ 103,700 | $ 103,700 |  |  |  |
Over-Allotment Option [Member] | American Depositary Shares [Member] |  |  |  |  |  |  |
Number of share issued, ADS | shares | 8,175,750 |  |  |  |  |  |
Proceeds from initial public offering | $ | $ 114,500 |  |  |  |  |  |
Common stock shares issuable | shares | 768,350 |  |  |  |  |  |
Share price | $ / shares | $ 14.00 |  |  |  |  |  |

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