Stock Incentive Plan and Employee Stock Purchase Plan - ESPP (Details) - USD ($)	12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014
Other disclosures
Share-based compensation expense	$ 13,629,000	$ 12,638,000	$ 13,930,000
ESPP
Stock Incentive Plan
Purchase price expressed as percentage of fair market value of common stock	85.00%
Other disclosures
Share-based compensation expense		$ 1,200,000	$ 1,300,000	$ 1,300,000
Shares issued under the ESPP		700,000	700,000
Weighted average fair value (in dollars per share)		$ 3.84	$ 4.92
Unrecognized compensation cost		$ 600,000
Weighted average period for recognition of compensation costs		7 months 6 days
ESPP | Maximum
Stock Incentive Plan
Payroll deductions as percentage of salaries	10.00%
Number of shares per period up to which employees may purchase	2,500
Value of shares up to which employees may purchase in any calendar year	$ 25,000
Weighted average assumptions used for determining fair value of options
Risk-free interest rate (as a percent)	0.70%	0.70%	0.26%
Expected term (in years)	1 year	1 year	1 year
Expected volatility (as a percent)	42.00%	49.10%	41.30%
ESPP | Minimum
Weighted average assumptions used for determining fair value of options
Risk-free interest rate (as a percent)	0.49%	0.51%	0.07%
Expected term (in years)	6 months	6 months	6 months
Expected volatility (as a percent)	24.60%	33.30%	27.10%