Summary of Significant Accounting Policies - Share-Based Compensation, Net Loss Per Common Share and Income Taxes (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended				12 Months Ended
	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015	Apr. 17, 2014	Feb. 28, 2013	Aug. 01, 2011
Anti-dilutive securities excluded from computation of earnings per share
Anti-dilutive securities excluded from the computation of diluted net income (loss) per share (in shares)					16,068	16,222	18,294
Numerator:
Net loss used to compute basic and diluted loss per share					$ (29,579)	$ (25,504)	$ (40,209)
Denominator:
Weighted average shares used to compute basic and diluted loss per share	83,179	82,913	82,328	81,576	82,495	80,509	78,277
Income Taxes
Reduction in uncertain tax position due to lapse of various statutes of limitation					$ 100
Subsequent period within which no material changes in unrecognized tax benefits are expected					12 months
3.75% Convertible Notes
Anti-dilutive securities excluded from computation of earnings per share
Interest rate (as a percent)	3.75%				3.75%	3.75%				3.75%
Conversion shares outstanding principal amount excluded in the potentially diluted shares					3,900
3.50% Convertible Notes
Anti-dilutive securities excluded from computation of earnings per share
Interest rate (as a percent)	3.50%				3.50%	3.50%		3.50%	3.50%
Anti-dilutive securities excluded from the computation of diluted net income (loss) per share (in shares)					8,378	8,378	8,378
3.50% Series A Convertible Notes
Anti-dilutive securities excluded from computation of earnings per share
Interest rate (as a percent)	3.50%				3.50%	3.50%		3.50%
Anti-dilutive securities excluded from the computation of diluted net income (loss) per share (in shares)							2,896
Conversion shares outstanding principal amount excluded in the potentially diluted shares					13,200
Stock options
Anti-dilutive securities excluded from computation of earnings per share
Expiration period					10 years
Anti-dilutive securities excluded from the computation of diluted net income (loss) per share (in shares)					2,463	2,377	2,537
RSUs, PSUs and MSUs
Anti-dilutive securities excluded from computation of earnings per share
Anti-dilutive securities excluded from the computation of diluted net income (loss) per share (in shares)					5,227	5,467	4,483