Stock-based compensation (Tables)

3 Months Ended

Mar. 31, 2015

	Number of shares available for grant			Total options outstanding			Weighted Average Exercise Price		Aggregate Intrinsic Value
Balance at December 31, 2014		32,863			19,600		$	0.10	$	26,656
Exercised					(162	)		0.12		(217	)
Granted		(1,750	)		1,750			1.02		779
Cancelled		44			(44	)		0.11		(59	)
Balance at March 31, 2015		31,157			21,144		$	0.18	$	27,159