Estimated Fair Value of Financial Instruments - Schedule of Carrying Amounts (Details) - Level 2 - USD ($) $ in Thousands	Mar. 31, 2018	Jun. 30, 2017
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Convertible Senior Notes	$ 19,726	$ 98,084
Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Convertible Senior Notes	$ 57,087	$ 180,950

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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