Accrued liability for ESPP plan employee contributions for shares not yet purchased.

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- Definition

Exercise price per share or per unit of warrants or rights exercised

+ References

No definition available.

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- Definition

Number of warrants or rights exercised.

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No definition available.

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- Definition

Maximum annual eligible purchase amount under the Employer Stock Purchase Plan in accordance with Section 423 of the Internal Revenue Code.

+ References

No definition available.

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- Definition

Percentage of the company's stock that must be acquired in order to for stock purchase rights to become exercisable.

+ References

No definition available.

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- Definition

Expiration date of outstanding warrants

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No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
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- Definition

Number of warrants or rights outstanding.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i))
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- Definition

Aggregate number of common shares reserved for future issuance.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ 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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- 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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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- Definition

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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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- Definition

Discount rate from fair value on offering date that participants pay for shares.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

+ References

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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).

+ 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 (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ 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 (d)(2)
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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ 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 (f)(2)(iii)
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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 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
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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

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

+ References

No definition available.

+ Details

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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.

+ 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)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5

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- Definition

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Stock Split
-URI http://asc.fasb.org/extlink&oid=6525746

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Stockholders' Equity - Additional Information (Detail)		12 Months Ended
Stockholders' Equity - Additional Information (Detail)	Sep. 15, 2015 shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) shares	Dec. 31, 2013 USD ($) $ / shares shares	Sep. 14, 2015 shares	Jun. 16, 2015 shares	Mar. 31, 2015 shares	Dec. 04, 2006
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum percentage before exercise								20.00%
Stock split of common stock	2
Number of shares available for issuance		8,700,000
Total fair value of restricted stock units vested \| $		$ 14,100,000	$ 7,000,000	$ 11,800,000
Employees share purchase plan, fair market value of common stock at beginning of offering period		85.00%
Employees share purchase plan, fair market value of common stock at end of purchase period		85.00%
Eligible employee purchases \| $		$ 25,000
Shares reserved for issuance		97,662
Shares issued in period		312,086
Employee withholdings for ESPP shares \| $		$ 1,700,000
Expected dividend yield		0.00%
Unrecognized stock-based compensation expense \| $		$ 87,200,000
Unrecognized stock-based compensation expense, weighted-average period for recognition		2 years 6 months
Warrants to purchase aggregate shares of common stock, Exercised				51,616
Common stock, Exercise price per share \| $ / shares				$ 0.39
Warrants to purchase aggregate shares of common stock, Outstanding		40,000
Common stock, Exercise price per share, Outstanding \| $ / shares		$ 3.47
Warrants expiration date		2017
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payments award, expiration term		10 years
Share-based payment awards, vesting period		4 years
Stock options granted		0	0	0
Stock appreciation rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of restricted stock units vested \| $		$ 5,730,000	$ 6,834,000	$ 9,955,000
Stock appreciation rights granted		0	0	0
Annual non-employee directors grants [Member] \| Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment awards, vesting period		1 year
Annual non-employee directors grants [Member] \| Restricted stock units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment awards, vesting period, descriptions		Restricted stock units generally vest in three equal installments on approximately the first, second and third anniversaries of the grant date, except for annual restricted stock unit grants to non-employee directors, which vest on approximately the first anniversary of the grant date.
Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance	47,700,000					23,850,000	21,150,000
Stock split of common stock	2
Equity Incentive Plan [Member] \| Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted		1,822,724
Equity Incentive Plan [Member] \| Restricted stock units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock appreciation rights granted		670,244
ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance	6,000,000				3,000,000