Number of employees granted awards under the stock based compensation plan of the entity.

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Intrinsic value of equity-based compensation awards exercised. Excludes stock and unit options.

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No definition available.

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Represents the change in the aggregate fair value of the liability amount of the redemption right of the awardees of vested awards in a stock based compensation arrangement.

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No definition available.

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Represents the change in the aggregate fair value of the liability amount of the redemption right of the awardees of vested awards in a stock based compensation arrangement.

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No definition available.

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Amount per share or per unit of equity securities to repurchase vested awards in a share-based compensation plan.

+ References

No definition available.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

The number of grants made 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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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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No definition available.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Share-Based Compensation - Additional Information (Detail) ¥ / shares in Units, $ / shares in Units, ¥ in Thousands, $ in Thousands				12 Months Ended
	Apr. 24, 2014 shares	Jan. 02, 2014 shares	May 26, 2011 shares	Dec. 31, 2017 CNY (¥) Employee ¥ / shares shares	Dec. 31, 2017 USD ($) Employee $ / shares shares	Dec. 31, 2016 CNY (¥) shares	Dec. 31, 2016 $ / shares shares	Dec. 31, 2015 CNY (¥)	Dec. 31, 2017 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expenses				¥ 73,316	$ 11,268	¥ 306,149		¥ 315,740
2014 Restricted Share Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares subject to award	122,545,665
Exercised				42,548	$ 6,539
Granted \| $ / shares					$ 0.78		$ 1.13
2014 Restricted Share Plan \| Restricted shares with an option feature
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted \| $ / shares					0.78
Forfeited \| $ / shares					$ 1.20
2013 Incentive Scheme
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares subject to award		64,497,718
Award scheme term		10 years
2013 Incentive Scheme \| Restricted shares with an option feature
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercised				24,201	$ 3,720
Granted \| $ / shares					$ 0.60
Unrecognized compensation costs				¥ 41,509					$ 6,380
Forfeited \| $ / shares					1.27
2011 Share Award Scheme
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award scheme term			10 years
Shares available to be granted in the future				5,226,718		4,793,807	4,793,807		5,226,718
2011 Share Award Scheme \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted \| $ / shares					$ 0.91		$ 1.61
Unrecognized compensation costs				¥ 4,979					$ 765
Expected period over which unamortized compensation costs is to be recognized				1 year 1 month 9 days	1 year 1 month 9 days
Forfeited \| $ / shares					$ 1.23
Granted				484,000	484,000
Total fair value of vested shares				¥ 21,149	$ 3,251	¥ 120,343		301,715
2011 Share Award Scheme \| Restricted shares with repurchase options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Repurchase price of vested shares \| ¥ / shares				¥ 4
Redemption right liability				¥ 596	92	652
Change in fair value of redemption right recorded as share-based compensation costs				27	4
Share-based compensation expenses				¥ 33	$ 5
2011 Share Award Scheme \| Restricted shares with repurchase options \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted				3,000,000	3,000,000
Number of employees \| Employee				2	2
Other Share Incentive Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs				¥ 436					$ 67
Expected period over which unamortized compensation costs is to be recognized				3 months 15 days	3 months 15 days
Total fair value of vested shares				¥ 7,888	$ 1,212	¥ 12,831		¥ 12,247
Other Share Incentive Awards \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted \| $ / shares							$ 1.62
Forfeited \| $ / shares					$ 1.83
Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ordinary shares, shares issued				415,250,897		410,608,263	410,608,263		415,250,897
Ordinary shares outstanding for exercised share awards				409,345,857		380,922,773	380,922,773		409,345,857
Common Class A [Member] \| 2014 Restricted Share Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ordinary shares, shares issued				11,542,980		3,265,470	3,265,470		11,542,980
Ordinary shares outstanding for exercised share awards				11,542,980		3,265,470	3,265,470		11,542,980
Unrecognized compensation costs				¥ 92,751					$ 14,256
Expected period over which unamortized compensation costs is to be recognized				2 years 3 months 26 days	2 years 3 months 26 days
Common Class A [Member] \| 2013 Incentive Scheme
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ordinary shares, shares issued				15,114,190		9,983,080	9,983,080		15,114,190
Ordinary shares outstanding for exercised share awards				15,114,190		9,983,080	9,983,080		15,114,190
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		5 years
Maximum [Member] \| 2014 Restricted Share Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	5 years
Maximum [Member] \| 2013 Incentive Scheme
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				1 year 9 months 18 days	1 year 9 months 18 days
Maximum [Member] \| 2011 Share Award Scheme
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares subject to award			100,000,000
Maximum [Member] \| 2011 Share Award Scheme \| Restricted shares with repurchase options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period				4 years	4 years	4 years