Income Taxes - Effective Income tax Rate (Details)	12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015
The effective income tax rate differs from the U.S. Federal statutory income tax rate
Federal statutory income tax rate	34.00%	35.00%	35.00%
State income taxes, net of federal benefit	5.90%	2.80%	2.00%
Foreign tax rate difference	(4.60%)	(2.30%)	(1.30%)
Tax return to provision true-up	0.60%	0.70%	1.30%
Other differences	(2.10%)	0.00%	0.00%
Permanent differences:
— stock based compensation	4.60%	0.90%	1.20%
— domestic production activities deduction	(3.30%)	(4.40%)	(1.60%)
— credit for increasing research activities	(0.90%)	(0.70%)	(3.80%)
— meals and entertainment	3.40%	1.00%	1.00%
— penalties	1.50%	0.00%	0.00%
— other	4.30%	(3.90%)	(0.70%)
Change in valuation allowance	1.30%	0.60%	0.00%
Net income tax provision	44.70%	29.70%	33.10%