Stock-Based Compensation (Details) (USD $)	12 Months Ended	1 Months Ended
Dec. 31, 2014	Apr. 30, 2011
2012 Plan
Stock-based compensation
Shares available for future issuance	1,453,253
2012 Plan \| Maximum
Stock-based compensation
Annual increase to the maximum number of shares (or other type of equity) approved (usually by shareholders and board of directors) for awards under the equity-based compensation plan	975,000
Annual increase to the maximum number of shares (or other type of equity) approved (usually by shareholders and board of directors) for awards under the equity-based compensation plan, as a percentage of the number of shares of the entity's common stock then outstanding	4.00%
2011 Plan \| Maximum
Stock-based compensation
Shares available for future issuance	679,622
Restricted stock purchase agreements \| Founder
Stock-based compensation
Shares issued		3,509,634
Purchase price (in dollars per share)		$ 0.002
Restricted stock purchase agreements \| Three co-founders
Stock-based compensation
Number of co-founders		3
Percentage of shares vesting on the grant date		25.00%
Restricted stock purchase agreements \| Two co-founders
Stock-based compensation
Number of co-founders		2
Percentage of the then-unvested shares that vested in connection with the Preferred Stock financing		25.00%

Represents the number of co-founders.

No definition available.

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- Definition

Represents the percentage of shares vesting on the grant date.

+ References

No definition available.

+ Details

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- Definition

Represents the percentage of the then-unvested shares that vested in connection with the Preferred Stock financing.

+ References

No definition available.

+ Details

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- Definition

Represents the annual increase to the maximum number of shares (or other type of equity) approved (usually by shareholders and board of directors) for awards under the equity-based compensation plan, as a percentage of the number of shares of the entity's common stock then outstanding.

+ 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

Price of a single share of a number of saleable stocks of a company.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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- Definition

Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

+ References

No definition available.

+ Details

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