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Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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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).

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

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Per share or per unit amount of equity securities issued.

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Equity Incentive Plans - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended				3 Months Ended		6 Months Ended
	Feb. 29, 2020	Feb. 28, 2019	Jul. 31, 2018	Jun. 30, 2015	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date estimated fair value of options granted					$ 5.14		$ 5.19
Net proceeds from stock option exercised							$ 420	$ 7
Stock-based compensation expenses					$ 2,674	$ 1,923	5,622	3,845
Proceeds							375	198
Issuance of common stock for services, amount					$ 310	$ 311	$ 310	$ 311
Warrants issued to purchase common stock				2,172,899
Common stock to be issued if warrants are exercised (in shares)				2,172,899
Purchase price of common shares				$ 0.125
Exercise price for warrants				$ 13.91
Warrant exercise period				5 years
Warrants exercised							0
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued under ESPP	75,804	83,046
Purchase price	$ 4.95	$ 2.39
Proceeds	$ 400	$ 200
Options to Purchase Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, granted					729,727		2,649,516
Number of options exercised					63,064	1,681	204,615	2,451
Net proceeds from stock option exercised					$ 200		$ 400
Issuance of common stock for services, shares					42,403		42,403	113,136
Issuance of common stock for services, amount					$ 300	$ 300	$ 300	$ 300
Performance-Based Restricted Stock Units (PRSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, granted			903,374		30,000
Number of shares, outstanding					849,328		849,328
Number of vested shares							0
Stock-based compensation expenses					$ 600		$ 1,400
Performance-Based Restricted Stock Units (PRSUs) [Member] \| Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, outstanding					30,000		30,000
Time Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, granted					0	0	0	0
Number of shares issued upon vesting of restricted stock units					0	85,609	0	85,609