Financial Instruments - Convertible Notes (Details) - USD ($) $ in Thousands	Aug. 07, 2017	Jun. 30, 2017	Jun. 30, 2016	Apr. 17, 2014	Feb. 28, 2013	Aug. 01, 2011
Carrying Value
Fair value measurement
Long term debt		$ 164,571	$ 210,412
Fair Value
Fair value measurement
Long term debt		$ 174,676	$ 233,194
3.75% Convertible Notes
Fair value measurement
Interest rate (as a percent)		3.75%	3.75%			3.75%
3.50% Convertible Notes
Fair value measurement
Interest rate (as a percent)		3.50%	3.50%	3.50%	3.50%
3.50% Series A Convertible Notes
Fair value measurement
Interest rate (as a percent)		3.50%	3.50%	3.50%
Existing 3.50% Convertible Notes
Fair value measurement
Interest rate (as a percent)	3.50%	3.50%
Non-recurring basis | Level 2 | 3.75% Convertible Notes | Carrying Value
Fair value measurement
Long term debt			$ 36,400
Non-recurring basis | Level 2 | 3.75% Convertible Notes | Fair Value
Fair value measurement
Long term debt			36,487
Non-recurring basis | Level 2 | 3.50% Convertible Notes | Carrying Value
Fair value measurement
Long term debt		$ 44,099	43,195
Non-recurring basis | Level 2 | 3.50% Convertible Notes | Fair Value
Fair value measurement
Long term debt		48,146	51,450
Non-recurring basis | Level 2 | 3.50% Series A Convertible Notes | Carrying Value
Fair value measurement
Long term debt		68,924	66,613
Non-recurring basis | Level 2 | 3.50% Series A Convertible Notes | Fair Value
Fair value measurement
Long term debt		$ 74,982	81,053
Non-recurring basis | Level 2 | Secured Loan | Carrying Value
Fair value measurement
Long term debt			64,204
Non-recurring basis | Level 2 | Secured Loan | Fair Value
Fair value measurement
Long term debt			$ 64,204
Non-recurring basis | Level 2 | Existing 3.50% Convertible Notes
Fair value measurement
Interest rate (as a percent)		3.50%
MidCap Revolving Credit Facility | Non-recurring basis | Level 2 | Carrying Value
Fair value measurement
Long term debt		$ 51,548
MidCap Revolving Credit Facility | Non-recurring basis | Level 2 | Fair Value
Fair value measurement
Long term debt		$ 51,548