Schedule of the computation of basic and diluted net income (loss) per share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Earnings Per Share [Abstract]
participating securities	4,433		4,433		26,463
Numerator:
Net loss	$ (7,891)	$ (3,102)	$ (21,288)	$ (8,623)
Denominator:
Weighted Average Number of Shares Outstanding, Basic and Diluted	25,432,000	24,747,000	25,243,000	24,530,000
Net loss per share
Earnings Per Share, Basic and Diluted	$ (0.31)	$ (0.13)	$ (0.84)	$ (0.35)