Common Stock Warrant Issued.

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- Definition

Warrant Term.

+ References

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))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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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)

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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)

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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

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

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).

+ References

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-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.

+ References

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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.

+ 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)

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

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- Definition

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

+ 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)(1)(iv)(1)

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

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- Definition

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

+ References

No definition available.

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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-Topic 718

-SubTopic 10

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-Subparagraph (c)(1)(i)-(ii)

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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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- Definition

Percentage of vesting of share-based compensation awards.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

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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)

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- Definition

Number of options vested.

+ References

No definition available.

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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.

+ References

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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-Name Accounting Standards Codification

-Glossary Stock Split

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Stock-Based Compensation - Additional Information (Detail) $ / shares in Units, $ in Thousands		1 Months Ended				3 Months Ended		9 Months Ended
	Jul. 10, 2015	Jul. 31, 2015 $ / shares shares	Jun. 30, 2015	Mar. 31, 2015 $ / shares shares	Mar. 31, 2014 shares	Sep. 30, 2015 USD ($) $ / shares shares	Sep. 30, 2014 shares	Sep. 30, 2015 USD ($) $ / shares shares	Dec. 31, 2014 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Forward stock split of its outstanding common stock	1.8515							1.8515
Officer \| Initial Public Offering
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Forward stock split of its outstanding common stock		1
Officer \| Vest over a 40-month service period beginning on April 1, 2015 \| Initial Public Offering
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement, Award Vesting Rights, Percentage		50.00%
Officer \| Vest based on the achievement of various milestones \| Initial Public Offering
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement, Award Vesting Rights, Percentage		50.00%
Common Class A
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock price of warrants \| $ / shares						$ 2.44		$ 2.44
Forward stock split of its outstanding common stock			1.00
2015 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for issuance		4,257,572
Additional Shares reserved for issuance		8,439,494
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares granted to employee								5,713,899
Shares granted at an exercise price \| $ / shares								$ 7.92
Aggregate intrinsic value of stock options exercised \| $						$ 882
Unrecognized compensation cost related to non-vested stock options \| $						$ 33,079		$ 33,079
Weighted-average period for recognition								2 years 1 month 2 days
Stock option outstanding						9,811,356		9,811,356	5,137,914
Employee Stock Option \| Officer \| Initial Public Offering
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares granted at an exercise price \| $ / shares		$ 25.00
Granted option to purchase common stock		1,455,450
Employee Stock Option \| Common Class A \| Officer
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares granted to employee				1,851,500
Shares granted at an exercise price \| $ / shares				$ 2.20
Option vesting period				4 years
Warrant Term				4 years
Stock price of warrants \| $ / shares				$ 2.00
Option vested								9,442,650
Employee Stock Option \| Common Class A \| Officer \| Vest over a 40-month service period beginning on April 1, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants issued to purchase common shares				7,406,000
Employee Stock Option \| Common Class A \| Officer \| Vest based on the achievement of various milestones
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants issued to purchase common shares				10,183,250
Employee Stock Option \| Common Class A \| Maximum \| Officer
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants issued to purchase common shares				17,589,250
Employee Stock Option \| 2014 Equity Incentive Plan \| Common Class A
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance					11,109,000
Employee Stock Option \| 2014 Equity Incentive Plan \| Common Class A \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Maximum expiration period of grant date fair value of incentive plan					10 years
Outstanding Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Grants of restricted stock								970,300
Unrecognized compensation cost related to non-vested stock options \| $						$ 10,108		$ 10,108
Weighted-average period for recognition								9 months 29 days
Outstanding Restricted Stock Units \| Officer \| Initial Public Offering
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Grants of restricted stock		970,300
Non Employee Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares granted to employee							0	0
Option vested								136,933
Stock option outstanding						347,155		347,155