Summary of business and significant accounting policies - Geographical Information (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Total revenue	$ 35,351	$ 64,496	$ 73,875	$ 66,629	$ 51,703	$ 48,540	$ 50,160	$ 46,252	$ 240,351	$ 196,655	$ 191,234
Property and equipment, net	4,319				5,583				4,319	5,583
United States
Disaggregation of Revenue [Line Items]
Total revenue									175,427	157,422	169,318
Property and equipment, net	2,519				2,679				2,519	2,679
International
Disaggregation of Revenue [Line Items]
Total revenue									64,924	39,233	$ 21,916
Property and equipment, net	$ 1,800				$ 2,904				$ 1,800	$ 2,904