v3.19.1

Net loss per share attributable to common stockholders (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Apr. 01, 2013
Numerator:
Net loss attributable to common stockholders, basic and diluted	$ (5,153)	$ (3,229)
Denominator:
Weighted average common stock, basic and diluted (in shares)	43,527	41,330
Net loss per share attributable to common stockholders:
Basic and diluted (in dollars per share)	$ (0.12)	$ (0.08)
Stock repurchase program
Remaining approved amount for repurchases	$ 5,180
Maximum
Stock repurchase program
Amount of common stock approved by the entity for a stock repurchase program			$ 10,000

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount of stock repurchase plan authorized.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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