401(K) Profit Sharing Plan (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015
Profit sharing plan
Contributions expensed	$ 1.3	$ 1.2	$ 1.1
Full-time Employees
Profit sharing plan
Eligible service period (in months)	6 months
Part-time Employees
Profit sharing plan
Eligible service period (in months)	12 months
Eligible minimum service period (in hours)	1000 hours
Minimum
Profit sharing plan
Employee's contribution (as a percent)	1.00%
Maximum
Profit sharing plan
Employee's contribution (as a percent)	75.00%
Match contribution by employer (as a percent)	4.00%