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Share-Based Compensation - Additional Information (Detail) $ / shares in Units, ¥ in Thousands, $ in Thousands |  |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |  |
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Jan. 17, 2020 CNY (¥) shares | Oct. 31, 2019 | Feb. 22, 2019 CNY (¥) shares | Feb. 22, 2019 USD ($) $ / shares shares | Oct. 31, 2017 shares | Oct. 31, 2016 $ / shares shares | Jun. 30, 2016 CNY (¥) shares | Sep. 30, 2020 USD ($) $ / shares shares | Sep. 30, 2020 CNY (¥) shares | Sep. 30, 2020 USD ($) $ / shares shares | Sep. 30, 2019 CNY (¥) | Sep. 30, 2019 USD ($) | Dec. 31, 2019 CNY (¥) shares | Dec. 31, 2019 USD ($) $ / shares shares | Dec. 31, 2017 $ / shares shares | Dec. 31, 2016 shares | Jul. 15, 2020 shares | Oct. 29, 2019 $ / shares | Dec. 31, 2018 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense |  |  |  |  |  |  |  |  | ¥ 392,576 | $ 57,820 | ¥ 515,193 |  | ¥ 515,203 |  |  |  |  |  |
Estimated fair value of Company's ordinary shares | $ / shares |  |  |  |  |  | $ 0.77 |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, stock options granted |  |  |  |  |  |  |  |  | 72,000 | 72,000 |  |  |  |  |  |  |  |  |
Common shares, par value | $ / shares |  |  |  |  |  |  |  | $ 0.0001 |  | $ 0.0001 |  |  |  | $ 0.0001 | $ 0.0001 |  |  |  | $ 0.0001
Stock options granted |  |  |  |  |  |  |  |  | 72,000 | 72,000 |  |  |  |  |  |  |  |  |
Number of additional shares authorized |  |  |  |  |  |  |  |  | 91,051 | 91,051 |  |  |  |  |  |  |  |  |
Third Venture [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 369,301 |  |  |
General and Administrative Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense |  |  |  |  |  |  |  |  | ¥ 167,957 | $ 24,737 | 514,726 |  | 514,733 |  |  |  |  |  |
Research and Development Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense |  |  |  |  |  |  |  |  | 224,619 | 33,083 | 467 |  | 470 |  |  |  |  |  |
Founders [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4,019,554 |  |  |
Director [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common shares, par value | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.0001 |
Stock options, repurchased during the period, average price | $ / shares |  |  |  | $ 5.63 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock options, repurchased during the period, total consideration |  |  | ¥ 148,308 | $ 21,902 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restricted Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense |  |  |  |  |  |  |  |  | 0 | 0 | 1,556 |  | 1,566 |  |  |  |  |  |
Share based payment award, maximum shares authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,686,081 |  |
Restricted Shares [Member] | General and Administrative Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense |  |  |  |  |  |  |  |  | 0 | 0 | 1,089 |  | 1,096 |  |  |  |  |  |
Restricted Shares [Member] | Research and Development Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense |  |  |  |  |  |  |  |  | 0 | $ 0 | 467 |  | ¥ 470 |  |  |  |  |  |
Restricted Shares [Member] | Tranche One [Member] | Third One Third Portion [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  |  |  |  | 25.00% |  |  |  |  |  |  |  |  |  |  |
Restricted Shares [Member] | Tranche Two [Member] | Third One Third Portion [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  |  |  |  | 25.00% |  |  |  |  |  |  |  |  |  |  |
Restricted Shares [Member] | Tranche Three [Member] | Third One Third Portion [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  |  |  |  | 25.00% |  |  |  |  |  |  |  |  |  |  |
Restricted Shares [Member] | One Performance Condition [Member] | Third One Third Portion [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  |  |  |  | 20.00% |  |  |  |  |  |  |  |  |  |  |
Restricted Shares [Member] | Two Performance Conditions [Member] | Third One Third Portion [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  |  |  |  | 40.00% |  |  |  |  |  |  |  |  |  |  |
Restricted Shares [Member] | Three Performance Conditions [Member] | Third One Third Portion [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  |  |  |  | 60.00% |  |  |  |  |  |  |  |  |  |  |
Restricted Shares [Member] | Four Performance Conditions [Member] | Third One Third Portion [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  |  |  |  | 80.00% |  |  |  |  |  |  |  |  |  |  |
Restricted Shares [Member] | Tranche Four [Member] | Third One Third Portion [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  |  |  |  | 25.00% |  |  |  |  |  |  |  |  |  |  |
Restricted Shares [Member] | Founders [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense | ¥ |  |  |  |  |  |  | ¥ 18,700 |  |  |  |  |  |  |  |  |  |  |  |
Number of shares granted |  |  |  |  |  |  | 3,650,253 |  |  |  |  |  |  |  |  |  |  |  |
Number of shares cancelled |  |  |  |  |  | 87,441 |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares outstanding |  |  |  |  |  | 3,932,113 |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares held, restriction percentage |  |  |  |  |  | 70.00% |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting period |  | 3 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restricted Shares [Member] | Founders [Member] | Tranche One [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  |  | 20.00% |  |  |  |  |  |  |  |  |  |  |  |  |
Restricted Shares [Member] | Founders [Member] | Tranche Two [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  |  | 20.00% |  |  |  |  |  |  |  |  |  |  |  |  |
Restricted Shares [Member] | Founders [Member] | Tranche Three [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  |  | 30.00% |  |  |  |  |  |  |  |  |  |  |  |  |
Employee Stock Option [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, stock options surrendered, exercise price | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1.0 |  |  |  |
Employee Stock Option [Member] | Director [Member] | General and Administrative Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense |  |  |  |  |  |  |  |  |  |  | ¥ 148,308 | $ 21,902 |  |  |  |  |  |  |
Employee Stock Option [Member] | Lei Fang [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, stock options surrendered |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 130,000 |  |  |  |
2019 Share Incentive Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense | ¥ |  |  |  |  |  |  |  |  | ¥ 741 |  |  |  |  |  |  |  |  |  |
Share based payment award, maximum shares authorized |  |  |  |  |  |  |  |  |  |  |  |  |  | 100,000 |  |  |  |  |
Share based payment award, stock options granted |  |  |  |  |  |  |  |  | 72,000 | 72,000 |  |  |  |  |  |  |  |  |
Stock options granted |  |  |  |  |  |  |  |  | 72,000 | 72,000 |  |  |  |  |  |  |  |  |
Stock options, exercise price | $ / shares |  |  |  |  |  |  |  |  |  | $ 6.09 |  |  |  |  |  |  |  |  |
2017 Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares granted | 9,609,084 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, maximum shares authorized | 9,609,084 |  |  |  | 13,376,865 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, stock options surrendered, exercise price | $ / shares |  |  |  |  |  |  |  |  |  | $ 1.00 |  |  |  |  |  |  |  |  |
Stock options exercisable |  |  |  |  |  |  |  | 8,047,548 |  | 8,047,548 |  |  |  | 0 |  |  |  |  |
Number of shares unvested | 332,566 |  |  |  |  |  |  |  | 336,377 | 336,377 |  |  |  |  |  |  |  |  |
Total number of shares unvested | 332,566 |  |  |  |  |  |  |  | 336,377 | 336,377 |  |  |  |  |  |  |  |  |
Exercise of stock options, shares |  |  |  |  |  |  |  |  | 115,888 | 115,888 |  |  | 0 | 0 |  |  |  |  |
2017 Plan [Member] | General and Administrative Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense | ¥ |  |  |  |  |  |  |  |  | ¥ 56,019 |  |  |  |  |  |  |  |  |  |
2017 Plan [Member] | Research and Development Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense | ¥ |  |  |  |  |  |  |  |  | 69,204 |  |  |  |  |  |  |  |  |  |
2017 Plan [Member] | Senior Management Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares unvested | 83,142 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total number of shares unvested | 83,142 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2017 Plan [Member] | Employee Stock Option [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense | ¥ |  |  |  |  |  |  |  |  | ¥ 0 |  |  |  |  |  |  |  |  |  |
Share based payment award, stock options granted |  |  |  |  |  |  |  |  | 0 | 0 |  |  | 640,000 | 640,000 |  |  |  |  |
Stock options granted |  |  |  |  |  |  |  |  | 0 | 0 |  |  | 640,000 | 640,000 |  |  |  |  |
2017 Plan [Member] | Employee Stock Option [Member] | Tranche Two [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  | 50.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |
2017 Plan [Member] | Employee Stock Option [Member] | Tranche Three [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  | 50.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |
2018 Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense | ¥ 91,051 |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 |  |  |  |  |
Number of shares granted | 11,005,888 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, maximum shares authorized |  |  | 14,005,745 | 14,005,745 |  |  |  |  |  |  |  |  |  | 15,452,620 |  |  |  |  |
Stock options, repurchased during the period |  |  |  |  |  |  |  |  | 454,940 | 454,940 |  |  | 454,940 | 454,940 |  |  |  |  |
Stock options exercisable |  |  |  |  |  |  |  | 10,166,671 |  | 10,166,671 |  |  |  |  |  |  |  |  |
2018 Plan [Member] | General and Administrative Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense | ¥ |  |  |  |  |  |  |  |  | ¥ 46,312 |  |  |  | ¥ 365,329 |  |  |  |  |  |
2018 Plan [Member] | Research and Development Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense | ¥ |  |  |  |  |  |  |  |  | ¥ 66,496 |  |  |  |  |  |  |  |  |  |
2018 Plan [Member] | Tranche One [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  | 50.00% | 50.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2018 Plan [Member] | Tranche Two [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  | 50.00% | 50.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2018 Plan [Member] | Dr. Zang [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, stock options granted exercise price | $ / shares |  |  |  | $ 1.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2018 Plan [Member] | Director [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Options, Vested And Exercisable Number |  |  | 10,893,028 | 10,893,028 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2018 Plan [Member] | Senior Management Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares unvested | 2,544,917 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total number of shares unvested | 2,544,917 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2018 Plan [Member] | Restricted Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares granted |  |  |  |  |  |  |  |  | 1,328,120 | 1,328,120 |  |  |  |  |  |  |  |  |
Share based payment award, stock options granted |  |  |  |  |  |  |  |  | 1,328,120 | 1,328,120 |  |  |  |  |  |  |  |  |
Share based payment award, stock options granted exercise price | $ / shares |  |  |  |  |  |  |  |  |  | $ 1.00 |  |  |  |  |  |  |  |  |
Stock options granted |  |  |  |  |  |  |  |  | 1,328,120 | 1,328,120 |  |  |  |  |  |  |  |  |
2018 Plan [Member] | Employee Stock Option [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based compensation by share based payment arrangement restricted stock units granted |  |  |  |  |  |  |  |  | 1,328,120 | 1,328,120 |  |  |  |  |  |  |  |  |
2018 Plan [Member] | Employee Stock Option [Member] | General and Administrative Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense | ¥ |  |  |  |  |  |  |  |  | ¥ 42,644 |  |  |  |  |  |  |  |  |  |
2018 Plan [Member] | Employee Stock Option [Member] | Research and Development Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense | ¥ |  |  |  |  |  |  |  |  | 65,259 |  |  |  |  |  |  |  |  |  |
Amended 2017 Plan [Member] | Director [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock options, repurchased during the period |  |  | 3,435,215 | 3,435,215 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Options, Vested And Exercisable Number |  |  | 3,435,215 | 3,435,215 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2020 Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense | ¥ |  |  |  |  |  |  |  |  | ¥ 2,052 |  |  |  |  |  |  |  |  |  |
Share based payment award, maximum shares authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10,760,513 |  |
Share based payment award, stock options granted |  |  |  |  |  |  |  |  | 1,068,733 | 1,068,733 |  |  |  |  |  |  |  |  |
Stock options granted |  |  |  |  |  |  |  |  | 1,068,733 | 1,068,733 |  |  |  |  |  |  |  |  |
Stock options exercisable |  |  |  |  |  |  |  | 0 |  | 0 |  |  |  |  |  |  |  |  |
2020 Plan [Member] | General and Administrative Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense | ¥ |  |  |  |  |  |  |  |  | ¥ 3,606 |  |  |  |  |  |  |  |  |  |
2020 Plan [Member] | Tranche One [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  |  |  |  | 25.00% |  |  |  |  |  |  |  |  |  |  |
2020 Plan [Member] | Tranche Two [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  |  |  |  | 25.00% |  |  |  |  |  |  |  |  |  |  |
2020 Plan [Member] | Tranche Three [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  |  |  |  | 25.00% |  |  |  |  |  |  |  |  |  |  |
2020 Plan [Member] | Tranche Four [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting percentage |  |  |  |  |  |  |  | 25.00% |  |  |  |  |  |  |  |  |  |  |
2020 Plan [Member] | Restricted Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based compensation by share based payment arrangement restricted stock units granted |  |  |  |  |  |  |  |  | 3,564,798 | 3,564,798 |  |  |  |  |  |  |  |  |
2020 Plan [Member] | Restricted Shares [Member] | Third One Third Portion [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based comensation equity instruments other than options aggregate fair value vested in period | $ |  |  |  |  |  |  |  | $ 2,000,000 |  |  |  |  |  |  |  |  |  |  |
Number of days for calculating the weighted average market value of shares |  |  |  |  |  |  |  | 30 days |  |  |  |  |  |  |  |  |  |  |
2020 Plan [Member] | Restricted Shares [Member] | Second One Third Portion [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of days for calculating the weighted average market value of shares |  |  |  |  |  |  |  | 30 days |  |  |  |  |  |  |  |  |  |  |
Maximum Percentage Reduction In The Weighted Average Market Value Of Shares |  |  |  |  |  |  |  | 20.00% |  |  |  |  |  |  |  |  |  |  |
2020 Plan [Member] | Restricted Shares [Member] | General and Administrative Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense | ¥ |  |  |  |  |  |  |  |  | ¥ 20,189 |  |  |  |  |  |  |  |  |  |
2020 Plan [Member] | Restricted Shares [Member] | Research and Development Expense [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense | ¥ |  |  |  |  |  |  |  |  | ¥ 20,054 |  |  |  |  |  |  |  |  |  |
2020 Plan [Member] | Employee Stock Option [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award, vesting period |  |  | 2 years | 2 years | 3 years |  |  |  |  |  |  |  |  |  |  |  |  |  |

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