Closing price per share.

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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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No definition available.

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- Definition

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No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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No definition available.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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No definition available.

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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.

+ References

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-Paragraph 2
-Subparagraph (a)(1)
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Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

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- Definition

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).

+ References

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

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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- 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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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

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- Definition

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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- Definition

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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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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- Definition

Percentage of vesting of share-based compensation awards.

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-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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-Name Accounting Standards Codification
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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, 2016 CNY (¥) shares	Dec. 31, 2016 USD ($) $ / shares shares	Nov. 30, 2016 CNY (¥)	Nov. 30, 2016 USD ($)	Dec. 31, 2015 CNY (¥)	Dec. 31, 2015 $ / shares	Dec. 31, 2014 CNY (¥)	Dec. 31, 2014 $ / shares	Dec. 31, 2016 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Closing stock price \| $ / shares									$ 25.28
Aggregate intrinsic value of options exercised	¥ 246,754	$ 35,540			¥ 623,605		¥ 693,878
Weighted average fair value per option granted \| $ / shares		$ 14.62				$ 0.00		$ 34.57
The total grant date fair value of options vested	25,168	$ 3,625			37,582		29,968
Aggregate fair value of outstanding options at the grant date	232,528								$ 33,491
Unrecognized share-based compensation expenses	¥ 160,640								$ 23,137
Incremental compensation cost			¥ 53,896	$ 7,763
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value per option granted \| $ / shares		$ 15.26						34.59
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 18 days	3 years 3 months 18 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 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 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	7,843,100								7,843,100
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	3,350,000								3,350,000
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	4,890,000	4,890,000
Stock Options [Member] \| 2016 Plan II [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	3,000,000	3,000,000
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 26 days	2 years 9 months 26 days
Aggregate fair value of the outstanding restricted shares	¥ 385,656	$ 55,546
Unrecognized compensation expense	267,389								$ 38,512
Weighted average grant date fair value, Granted \| $ / shares		$ 22.30				$ 34.70		$ 37.30
Grant date fair value of restricted shares vested	¥ 131,861	$ 18,992			¥ 38,104		¥ 7,925