Summary of business and significant accounting policies - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Total revenue	$ 69,596	$ 66,629
Product
Disaggregation of Revenue [Line Items]
Total revenue	56,809	55,990
Services
Disaggregation of Revenue [Line Items]
Total revenue	12,787	10,639
Point in Time | On-board automotive navigation solutions
Disaggregation of Revenue [Line Items]
Total revenue	56,809	55,990
Over Time | Brought-in automotive navigation solutions (over time)
Disaggregation of Revenue [Line Items]
Total revenue	10,914	6,222
Over Time | Automotive maintenance and support and other (over time)
Disaggregation of Revenue [Line Items]
Total revenue	90	1,669
Over Time | Mobile navigation services (over time)
Disaggregation of Revenue [Line Items]
Total revenue	$ 1,783	$ 2,748