Summary of business and significant accounting policies - Accumulated Other Comprehensive Income (Loss), Net of Tax (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	$ 106,481	$ 99,430	$ 90,640	$ 108,883
Other comprehensive income (loss) before reclassifications, net of tax			(513)
Amount reclassified from accumulated other comprehensive loss, net of tax			(14)
Other comprehensive income (loss), net of tax	(466)	287	(527)	132
Ending balance	101,909	93,897	101,909	93,897
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(1,538)	(2,010)	(1,477)	(1,855)
Ending balance	(2,004)	$ (1,723)	(2,004)	$ (1,723)
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance			(1,623)
Other comprehensive income (loss) before reclassifications, net of tax			(267)
Amount reclassified from accumulated other comprehensive loss, net of tax			0
Other comprehensive income (loss), net of tax			(267)
Ending balance	(1,890)		(1,890)
Unrealized Gains (Losses) on Available-for-Sale Securities
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance			146
Other comprehensive income (loss) before reclassifications, net of tax			(246)
Amount reclassified from accumulated other comprehensive loss, net of tax			(14)
Other comprehensive income (loss), net of tax			(260)
Ending balance	$ (114)		$ (114)