Income Taxes - Summary of Reconciliation of Tax Expense Computed by Applying Statutory Income Tax Rate to Pre-Tax Loss (Details) ¥ in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2021 CNY (¥)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 CNY (¥)	Dec. 31, 2019 CNY (¥)
Income Tax Disclosure [Abstract]
Income tax benefit at PRC statutory rate	¥ (1,502,997)	$ (235,853)	¥ (1,745,969)	¥ (2,556,222)
Effect of differing tax rates in different jurisdictions	377,604	59,254	291,884	293,976
Non-deductible expenses	181,972	28,555	238,899	436,312
Research and development super-deduction	(162,103)	(25,437)	(159,919)	(66,026)
Effect of PRC preferential tax rates and tax holiday	269,585	42,304	281,437	707,518
Other adjustments	(2,151)	(338)	(73,027)	104,484
Change in valuation allowance	934,635	146,665	1,189,971	1,131,810
Income tax expense	¥ 96,545	$ 15,150	¥ 23,276	¥ 51,852

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income exempt from income tax because of a tax holiday.

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