Maximum common stock purchase value for single employee.

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- Definition

Share based compensation arrangement by share based payment award automatic increase in number of shares authorized for issuance percentage.

+ References

No definition available.

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- Definition

Number of shares subject to vesting restrictions on grant date.

+ References

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

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)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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- Definition

Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

+ References

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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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

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

+ Details

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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

+ Details

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- Definition

General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

+ 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)

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

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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.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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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

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 weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

+ 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

+ Details

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

+ References

+ Details

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- Definition

Number of options vested.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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Stock Incentive Plans - Additional Information (Details) - USD ($)	1 Months Ended	9 Months Ended
	Feb. 28, 2013	Sep. 30, 2015	Apr. 14, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2012
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance		3,490,967			4,560,802
Number of share issued from ESPP		0
Common stock, shares issued		13,903,536			1,494,506
Common stock value issued		$ 4,000			$ 3,000
Weighted average grant date fair values of stock options granted		$ 5.57
Grant date fair value of stock options, vested		$ 1,700,000
Unrecognized share-based compensation expense of unvested employee stock options		$ 4,700,000
Unvested stock options, Unrecognized cost expected to be recognized, Recognition Period		2 years 8 months 12 days
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance		245,168	245,168
Automatic annual increase in shares authorized for issuance in equity incentive plan		1.00%
Equity incentive plan, description		In addition, the number of shares of stock available for issuance under the ESPP will be automatically increased each January 1, beginning on January 1, 2016, by the lesser of (i) 1% of the outstanding number of shares of the Company’s common stock on the immediately preceding December 31, or (ii) 490,336 shares.
Price of stock option as percentage of estimated fair value of shares on date of grant		85.00%
Common stock shares outstanding		490,336
Percentage of employee payroll deduction under the stock plan		15.00%
Maximum common stock purchase value for employee		$ 25,000
Unrecognized share-based compensation expense of unvested employee stock options		$ 300,000
Unvested stock options, Unrecognized cost expected to be recognized, Recognition Period		1 year 8 months 12 days
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares issued							385,825
Common stock value issued							$ 980
Vested shares		256,614
Shares subject to repurchase		14,718
Restricted Stock \| Employees and consultants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares issued		0				78,812
Restricted Stock \| Weighted Average \| Employees and consultants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares issued, weighted average purchase price per share						$ 0.13
Restricted Stock \| 5AM Ventures
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares issued							196,849
Restricted Stock \| Founders
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares issued							188,976
Vesting shares	118,110
2015 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance		1,634,456
Shares available for future grants or awards		1,838,333
Automatic annual increase in shares authorized for issuance in equity incentive plan		4.00%
Equity incentive plan, description		Upon effectiveness of the 2015 Plan, 194,564 shares were remaining under the 2013 Plan and were added to the 2015 Plan reserve. In addition, the number of shares of stock available for issuance under the 2015 Plan will be automatically increased each January 1, beginning on January 1, 2016, by 4% of the outstanding number of shares of the Company’s common stock on the immediately preceding December 31 or such lesser number as determined by the Company’s board of directors
Vesting terms outlined in the stock option agreement		4 years
Stock options grant period from date of grant		10 years
Price of stock option as percentage of estimated fair value of shares on date of grant		100.00%
2015 Equity Incentive Plan \| More than 10% of voting power
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Price of stock option as percentage of estimated fair value of shares on date of grant		110.00%
2013 Option and Grant Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future grants or awards				194,564