Share-based Compensation - Options Valuation (Details) - Stock options - $ / shares	12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Assumptions used to estimate fair values
Risk-free interest rate (as a percent)	2.90%	2.10%	1.10%
Expected volatility (as a percent)	58.40%	57.60%	55.60%
Forfeiture rate (as a percent)	6.50%	6.50%	6.50%
Expected term (in years)	5 years 3 months 18 days	5 years 4 months 24 days	5 years 2 months 12 days
Weighted average fair value (in dollars per share)	$ 6.52	$ 11.25	$ 15.33