Closing price per share.

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The period over which share-based awards are expected to vest.

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No of ordinary shares per ads after division.

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No of ordinary shares per ads before division.

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Represents the aggregate grant-date fair value of share-based awards reserved for issuance under the agreements awarded under the plan that validly exist and are outstanding, as of the balance sheet date.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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-SubTopic 10
-Section 50
-Paragraph 2
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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Number of shares authorized for issuance under share-based payment arrangement.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Share-Based Compensation - Additional Information (Detail) $ / shares in Units, ¥ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021 CNY (¥) Customer shares	Dec. 31, 2021 USD ($) Customer $ / shares	Dec. 31, 2020 $ / shares shares	Dec. 31, 2020 CNY (¥) Customer shares	Dec. 31, 2019 $ / shares	Dec. 31, 2019 CNY (¥)	Dec. 31, 2021 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Closing stock price \| $ / shares							$ 29.48
Aggregate intrinsic value of options exercised	¥ 27,950	$ 4,386		¥ 170,374		¥ 178,577
Weighted average fair value per option granted \| $ / shares		$ 23.00	$ 40.52		$ 45.26
The total grant date fair value of options vested	32,226	$ 5,057		¥ 58,092		79,197
Aggregate fair value of outstanding options at the grant date	¥ 89,242						$ 14,004
No of ordinary shares per Ads before division \| Customer	1	1		1
No of ordinary shares per Ads after division \| Customer	4	4
Unrecognized share-based compensation expenses	¥ 48,884						$ 7,671
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value per option granted \| $ / shares		$ 60.83	$ 44.69
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested options/restricted shares expected to be recognized over a weighted-average period	3 years 3 months 3 days	3 years 3 months 3 days
Stock Options [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	For share options and restricted shares with service condition or performance condition granted under the Plans, majority are subject to vesting schedules of approximately four years with 25% of the awards vesting each year and have a contractual term of ten years.	For share options and restricted shares with service condition or performance condition granted under the Plans, majority are subject to vesting schedules of approximately four years with 25% of the awards vesting each year and have a contractual term of ten years.
Stock Options [Member] \| 2011 Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards grant to employees, directors and consultants to purchase aggregate ordinary shares \| shares	31,372,400		7,843,100	7,843,100			31,372,400
Stock Options [Member] \| 2013 Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards grant to employees, directors and consultants to purchase aggregate ordinary shares \| shares	13,400,000		3,350,000	3,350,000			13,400,000
Stock Options [Member] \| 2016 Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards grant to employees, directors and consultants to purchase aggregate ordinary shares \| shares	19,560,000		4,890,000	4,890,000			19,560,000
Stock Options [Member] \| 2016 Plan II [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards grant to employees, directors and consultants to purchase aggregate ordinary shares \| shares	12,000,000		3,000,000	3,000,000			12,000,000
Options and Restricted Shares [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years	4 years
Original contractual term	10 years	10 years
Options and Restricted Shares [Member] \| Maximum [Member] \| Awards Vesting Percentage Each Year [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of awards vesting	25.00%	25.00%
Restricted Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested options/restricted shares expected to be recognized over a weighted-average period	2 years 9 months 29 days	2 years 9 months 29 days
Aggregate fair value of the outstanding restricted shares	¥ 454,972	$ 71,395
Unrecognized compensation expense	262,589						$ 41,206
Weighted average grant date fair value, Granted \| $ / shares		$ 50.79	$ 85.44		$ 85.30
Grant date fair value of restricted shares vested	¥ 165,675	$ 25,998		¥ 144,757		¥ 141,227