Indebtedness - Total Interest Expense Related to Notes (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Debt Instrument [Line Items]
Amortization of debt discount (non-cash)		$ 5,574	$ 9,396
Amortization of debt issue costs (non-cash)		819	1,022
Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Contractual interest expense (cash)	$ 711	1,194	2,135
Amortization of debt discount (non-cash)	3,188	5,574	9,396
Amortization of debt issue costs (non-cash)	296	494	888
Total interest expense	$ 4,195	$ 7,262	$ 12,419
Effective interest rate of the liability component	8.22%	8.45%	8.10%

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Amount of amortization expense attributable to debt issuance costs.

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The average effective interest rate during the reporting period.

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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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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs.

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