Share-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Employee stock purchase plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Available for future grants	2,618,416
Unrecognized share-based compensation expense, remaining weighted-average vesting periods	1 month 6 days
Eligible compensation under the Employee Stock Purchase Plan	15.00%
Purchase of maximum shares by employees under Employee Stock Purchase Plan	3,000
Purchase price of Employee Stock Purchase Plan as a percentage of fair value	90.00%
Unrecognized share-based compensation expense	$ 0.2
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized share-based compensation expense	$ 16.0	$ 24.6
Unrecognized share-based compensation expense, remaining weighted-average vesting periods	2 years 6 months	2 years 7 months 6 days
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period contractual term	4 years
RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized share-based compensation expense, remaining weighted-average vesting periods	3 years 1 month 21 days
Unrecognized share-based compensation expense	$ 36.8
2013 Equity incentive plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Available for future grants	10,054,774

Unrecognized cost of unvested share-based compensation awards.

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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- 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.

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- Definition

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

+ References

No definition available.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

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- Definition

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

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

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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.

+ References

No definition available.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

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

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- Definition

The highest quantity of shares an employee can purchase under the plan per period.

+ References

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- Definition

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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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

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