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Income Taxes - Additional Information (Detail) $ in Thousands |  | 12 Months Ended | 24 Months Ended | 36 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Apr. 01, 2018 | Dec. 31, 2021 CNY (¥) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 CNY (¥) | Dec. 31, 2019 CNY (¥) | Dec. 31, 2022 | Dec. 31, 2021 CNY (¥) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Income Tax Disclosure [Line Items] |  |  |  |  |  |  |  |  |
Statutory income tax rate |  | 25.00% | 25.00% | 25.00% | 25.00% |  |  |  |
Withholding Tax Rate On Dividend Distributed By Foreign Invested Enterprise To Its Immediate Holding Company |  | 10.00% | 10.00% |  |  |  |  |  |
Net tax operating losses from PRC subsidiaries |  | ¥ 2,700,300,000 |  |  |  |  | ¥ 2,700,300,000 |  |
Unrecognized tax benefits |  | 117,500,000 |  | ¥ 593,000 | ¥ 593,000 |  | 117,500,000 | $ 18,400 | $ 93
Unrecognized tax benefits on net basis against the deferred tax assets related to tax loss carry forwards |  | 108,100,000 |  | 600,000 |  |  | 108,100,000 | 17,000 |
Unrecognized tax benefits income tax penalties and interest expense |  | ¥ 0 |  | 0 |  |  |  |  |
Description of income tax examination |  | tax years ended December 31, 2018 through period ended December 31, 2021 remain open to examination by the PRC tax authorities. | tax years ended December 31, 2018 through period ended December 31, 2021 remain open to examination by the PRC tax authorities. |  |  |  |  |  |
Net Income (Loss) Attributable to Parent |  | ¥ (6,429,059,000) | $ (1,008,860) | (3,176,914,000) | ¥ (1,873,383,000) |  |  |  |
WFOE [Member] |  |  |  |  |  |  |  |  |
Income Tax Disclosure [Line Items] |  |  |  |  |  |  |  |  |
Unrecognized tax benefits |  | 9,400,000 |  |  |  |  | ¥ 9,400,000 | 1,500 |
Hong Kong [Member] | TwoTieredProfits Tax Regime [Member] |  |  |  |  |  |  |  |  |
Income Tax Disclosure [Line Items] |  |  |  |  |  |  |  |  |
Net Income (Loss) Attributable to Parent |  | ¥ 2,000,000 |  |  |  |  |  |  |
Hong Kong [Member] | Tax Rate Sixteen Point Five Percent [Member] | TwoTieredProfits Tax Regime [Member] |  |  |  |  |  |  |  |  |
Income Tax Disclosure [Line Items] |  |  |  |  |  |  |  |  |
Income tax rate | 16.50% |  |  |  |  |  |  |  |
Hong Kong [Member] | Profits On First HK Two Million [Member] | TwoTieredProfits Tax Regime [Member] |  |  |  |  |  |  |  |  |
Income Tax Disclosure [Line Items] |  |  |  |  |  |  |  |  |
Income tax rate |  | 8.25% | 8.25% |  |  |  |  |  |
China [Member] |  |  |  |  |  |  |  |  |
Income Tax Disclosure [Line Items] |  |  |  |  |  |  |  |  |
Statutory income tax rate |  | 25.00% | 25.00% |  |  |  |  |  |
Net tax operating losses from PRC subsidiaries | $ |  |  |  |  |  |  |  | $ 423,700 |
China [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |
Income Tax Disclosure [Line Items] |  |  |  |  |  |  |  |  |
Tax losses carry forwards period |  | 10 years | 10 years |  |  |  |  |  |
Operating Loss Carry Forwards Expiration Year |  | 2029 | 2029 |  |  |  |  |  |
China [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |
Income Tax Disclosure [Line Items] |  |  |  |  |  |  |  |  |
Tax losses carry forwards period |  | 5 years | 5 years |  |  |  |  |  |
Operating Loss Carry Forwards Expiration Year |  | 2024 | 2024 |  |  |  |  |  |
China [Member] | Qualifying Small Scale Enterprises [Member] |  |  |  |  |  |  |  |  |
Income Tax Disclosure [Line Items] |  |  |  |  |  |  |  |  |
Preferential tax rate |  | 20.00% | 20.00% |  |  |  |  |  |
Threshold Percentage Of Reduction Of Taxable Income Eligible For Qualifying Enterprises With Minimal Profits |  |  |  |  |  |  | 75.00% |  |
China [Member] | Qualifying Small Scale Enterprises [Member] | More Than 1 Million But Less Than 3 Million [Member] |  |  |  |  |  |  |  |  |
Income Tax Disclosure [Line Items] |  |  |  |  |  |  |  |  |
Threshold Percentage Of Reduction Of Taxable Income Eligible For Qualifying Enterprises With Minimal Profits |  |  |  |  |  | 12.50% | 50.00% |  |
Percentage Of Reduced CIT Rate Eligible For Qualifying Enterprises With Minimal profits |  |  |  |  |  |  | 20.00% |  |

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