Segments (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) segment	Dec. 31, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment			3
Revenue	$ 39,080	$ 52,001	$ 75,738	$ 94,228
Cost of revenue	22,311	28,727	43,158	52,203
Gross profit	$ 16,769	$ 23,274	$ 32,580	$ 42,025
Gross margin (in percent)	43.00%	45.00%	43.00%	45.00%
Automotive
Segment Reporting Information [Line Items]
Revenue	$ 26,838	$ 38,744	$ 52,142	$ 69,011
Cost of revenue	16,416	23,438	32,301	41,983
Gross profit	$ 10,422	$ 15,306	$ 19,841	$ 27,028
Gross margin (in percent)	39.00%	40.00%	38.00%	39.00%
Advertising
Segment Reporting Information [Line Items]
Revenue	$ 8,742	$ 8,208	$ 16,357	$ 14,753
Cost of revenue	4,402	3,919	7,814	7,445
Gross profit	$ 4,340	$ 4,289	$ 8,543	$ 7,308
Gross margin (in percent)	50.00%	52.00%	52.00%	50.00%
Mobile Navigation
Segment Reporting Information [Line Items]
Revenue	$ 3,500	$ 5,049	$ 7,239	$ 10,464
Cost of revenue	1,493	1,370	3,043	2,775
Gross profit	$ 2,007	$ 3,679	$ 4,196	$ 7,689
Gross margin (in percent)	57.00%	73.00%	58.00%	73.00%