Stockholders' equity (Tables)

12 Months Ended

Dec. 31, 2020

Stockholders' equity

Schedule of amount of shares of common stock reserved

	December 31,
	2020	2019
	(in thousands)
Outstanding stock options under the 2001 Plan	—	7
Outstanding stock options under the 2011 Plan	109	228
Outstanding RSUs under the 2011 Plan	951	633
Shares available for grant under the 2011 Plan	1,382	2,478
Total	2,442	3,346