Common Stock, Additional Capital Shares Reserved for Future Issuance

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- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Award Grant Date Anniversary

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No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

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-Topic 210
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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.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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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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- 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.

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No definition available.

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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- Definition

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

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- Definition

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

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No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Per share or per unit amount of equity securities issued.

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- Definition

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

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Share-Based Payments - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions					9 Months Ended
	Sep. 14, 2018	Aug. 07, 2018	Mar. 14, 2018	Jan. 01, 2018	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense					$ 2.9
Stock option to purchase shares (in shares)					3,055,900
Stock option exercise price (in USD per share)					$ 1.72
Options, forfeited (in shares)					1,111,941
Stock options \| President and Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option to purchase shares (in shares)		1,350,000
Stock option exercise price (in USD per share)		$ 1.60
Stock option term		10 years
Vesting period		4 years
Option grant date anniversary		1 year
Stock options \| President and Chief Executive Officer \| Vesting Period One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rights, percentage		25.00%
Stock options \| President and Chief Executive Officer \| Vesting Period Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 months
Vesting rights, percentage		6.25%
Stock options \| Former President and Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, forfeited (in shares)		536,250
2014 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in number of shares reserved for future issuance (in shares)				1,102,362
Shares available for issuance (in shares)					1,470,267
2014 ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expected to be recognized over a weighted-average period (in years)					3 years 2 months 5 days
Employee stock purchase plan issued during period (in shares)	11,427		9,565
Purchase price of shares authorized (in USD per share)	$ 0.95		$ 0.98