Represents the increase in number of shares available for grant during the period.

No definition available.

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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 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

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

+ References

No definition available.

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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.

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- Definition

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

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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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.

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- Definition

Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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Value, after forfeiture, of shares issued under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).

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Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended				6 Months Ended
	Jan. 31, 2019	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Share-based Compensation
Total grant date fair value of options vested		$ 527		$ 516		$ 1,300	$ 1,200
Shares available for future issuance (in shares)		156,184				156,184		638,227
Value of share issued		$ 827	$ 315	$ 137	$ 13
Weighted-average exercise price (per share)		$ 5.65				$ 5.65		$ 7.17
Number of stock options granted (in shares)						787,955
Options remained outstanding		2,416,629				2,416,629		1,931,903
Employees
Share-based Compensation
Weighted-average grant date fair value of options granted		$ 1.84		$ 4.34		$ 1.58	$ 4.07
2016 Employee Stock Purchase Plan
Share-based Compensation
Increase in number of shares available for grant	180,817
Shares available for future issuance (in shares)		554,343				554,343
Value of share issued		$ 50		$ 130		$ 50	$ 130
Number of shares issued (in shares)		22,474		22,405		22,474	22,405