Stockholders' equity - Summary of Stock Option Activity (Details) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Jun. 30, 2019 USD ($) $ / shares shares
Number of shares
Options outstanding (in shares) | shares	5,116
Granted (in shares) | shares	290
Exercised (in shares) | shares	(1,477)
Canceled or expired (in shares) | shares	(520)
Options outstanding (in shares) | shares	3,409
Options vested and expected to vest (in shares) | shares	3,341
Options exercisable (in shares) | shares	2,703
Weighted average exercise price per share
Options outstanding - Weighted average exercise price - Beginning balance (in dollars per share) | $ / shares	$ 6.48
Granted - Weighted average exercise price (in dollars per share) | $ / shares	5.10
Exercised - Weighted average exercise price (in dollars per share) | $ / shares	5.99
Canceled or expired - Weighted average exercise price (in dollars per share) | $ / shares	6.95
Options outstanding - Weighted average exercise price - Ending balance (in dollars per share) | $ / shares	6.49
Options vested and expected to vest - Weighted average exercise price (in dollars per share) | $ / shares	6.52
Options exercisable - Weighted average exercise price (in dollars per share) | $ / shares	$ 6.74
Weighted average remaining contractual life (years)
Options outstanding - Weighted average remaining contractual life	5 years 6 months 10 days
Options vested and expected to vest - Weighted average remaining contractual life	5 years 5 months 19 days
Options exercisable - Weighted average remaining contractual life	4 years 11 months 12 days
Aggregate intrinsic value
Options outstanding - Aggregate intrinsic value | $	$ 5,748
Options vested and expected to vest - Aggregate intrinsic value | $	5,564
Options exercisable - Aggregate intrinsic value | $	$ 4,000