Stock-Based Compensation - Additional Information (Detail) (USD $)	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Deferred Compensation Arrangement With Individual Share Based Payments [Line Items]
Unamortized share based compensation expected to be recognized over the remaining vesting period	$ 12,500,000
Unamortized share based compensation period for recognition	2 years 9 months 18 days
Weighted-average per share fair value of employee options granted	$ 12.46	$ 5.90	$ 4.70
Share based compensation, options weighted average exercise price	$ 18.31
Vesting period of stock options	4 years
Stock-based compensation	4,974,000	2,809,000	2,353,000
Number of common stock shares reserved for issuance under the 2013 Employee Stock Purchase Plan	4,903,323
Nonemployee Stock Options
Deferred Compensation Arrangement With Individual Share Based Payments [Line Items]
Share based compensation, options granted	32,943	6,380
Share based compensation, options weighted average exercise price	$ 19.88	$ 7.00
Vesting period of stock options	4 years
Stock-based compensation	$ 775,000	$ 144,000	$ 65,000
Employee Stock Purchase Plan
Deferred Compensation Arrangement With Individual Share Based Payments [Line Items]
Number of common stock shares reserved for issuance under the 2013 Employee Stock Purchase Plan	1,000,000
Percentage of common stock to employees at lesser of fair market value	85.00%
Percentage increase in number of common stock outstanding	2.00%

Share based compensation arrangement by share based payment award percentage increase in outstanding shares.

No definition available.

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- Definition

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 50

-Paragraph 1

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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-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.

+ References

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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)

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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).

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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-Paragraph 2

-Subparagraph (a)(3)

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- Definition

Net number of share options (or share units) granted during the period.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(1)

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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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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-Paragraph 2

-Subparagraph (d)(1)

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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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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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