Cash, cash equivalents and short-term investments - Summary of Fair Value and Unrealized Loss Position (Details) $ in Thousands	Mar. 31, 2020 USD ($) security	Jun. 30, 2019 USD ($) security
Fair Value
Less than 12 Months	$ 47,761	$ 5,093
12 Months or Greater	0	22,142
Total	47,761	27,235
Unrealized Losses
Less than 12 Months	(418)	(4)
12 Months or Greater	0	(41)
Total	$ (418)	$ (45)
Number of Positions
Less than 12 Months (securities) | security	131	11
12 Months or Greater (securities) | security	0	51
U.S. treasury securities
Fair Value
Less than 12 Months		$ 0
12 Months or Greater		2,992
Total		2,992
Unrealized Losses
Less than 12 Months		0
12 Months or Greater		(5)
Total		(5)
U.S. agency securities
Fair Value
Less than 12 Months		0
12 Months or Greater		998
Total		998
Unrealized Losses
Less than 12 Months		0
12 Months or Greater		(1)
Total		(1)
Asset-backed securities
Fair Value
Less than 12 Months	$ 7,671	0
12 Months or Greater	0	3,537
Total	7,671	3,537
Unrealized Losses
Less than 12 Months	(74)	0
12 Months or Greater	0	(11)
Total	(74)	(11)
Commercial paper
Fair Value
Less than 12 Months		493
12 Months or Greater		0
Total		493
Unrealized Losses
Less than 12 Months		(1)
12 Months or Greater		0
Total		(1)
Corporate bonds
Fair Value
Less than 12 Months	40,090	4,600
12 Months or Greater	0	14,615
Total	40,090	19,215
Unrealized Losses
Less than 12 Months	(344)	(3)
12 Months or Greater	0	(24)
Total	$ (344)	$ (27)