Net income (loss) per share - Calculation of basic and diluted net income (loss) per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2019		Jun. 30, 2018	[2]	Jun. 30, 2017	[2]
Net income applicable to common stockholders:
Net loss	$ (12,856)	$ (7,481)	$ (4,581)	$ (7,570)	$ (7,465)	$ (14,457)	$ (8,394)	$ (10,518)	$ (32,488)	[1]	$ (40,834)	[1]	$ (29,536)	[1]
Weighted average common shares used in computing net loss per share, basic and diluted (in shares)									45,577		44,498		43,343
Net loss per share, basic and diluted (in dollars per share)	$ (0.28)	$ (0.16)	$ (0.10)	$ (0.17)	$ (0.17)	$ (0.32)	$ (0.19)	$ (0.24)	$ (0.71)		$ (0.92)		$ (0.68)

[1] See Note 1 for a summary of adjustments. The cumulative effect adjustment to Accumulated Deficit and Total Stockholders' Equity related to the adoption of ASU No. 2014-09 (Topic 606) as of June 30, 2016 was $11.8 million.

[2] See Note 1 for a summary of adjustments.