Net loss per share attributable to common stockholders (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Numerator:
Net loss attributable to common stockholders, basic and diluted	$ (3,734)	$ (399)	$ (9,182)	$ (1,520)
Denominator:
Weighted average common stock, basic and diluted (in shares)	35,621	35,670	35,486	35,634
Net loss per share attributable to common stockholders:
Basic and diluted (in dollars per share)	$ (0.10)	$ (0.01)	$ (0.26)	$ (0.04)

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.

No definition available.

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