Net Loss Per Share (Schedule of Earnings Per Share, Basic and Diluted) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share Diluted [Line Items]
Net (loss) income	$ (9,065)	$ 4,376
Weighted-average shares used in per share calculation - basic	117,368	112,241
Weighted-average shares used in per share calculation - diluted	117,368	118,431
Net (loss) income per share:
Net (loss) income per share - basic	$ (0.08)	$ 0.04
Net (loss) income per share - diluted	$ (0.08)	$ 0.04
Options to purchase common stock
Earnings Per Share Diluted [Line Items]
Effect of potentially dilutive shares		1,760
Restricted Stock Units
Earnings Per Share Diluted [Line Items]
Effect of potentially dilutive shares		4,007
Employee Stock Purchase Plan shares
Earnings Per Share Diluted [Line Items]
Effect of potentially dilutive shares		423

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