Net Carrying Value of the Notes (Detail) - USD ($) $ in Thousands	Oct. 31, 2018	Jul. 31, 2018
Debt Instrument [Line Items]
Carrying amount of equity component (net of allocated debt issuance costs)	$ 26,961	$ 26,961
Principal amount of Notes	63,925	67,625
Unamortized debt discount	(1,690)	(2,843)
Unamortized debt issuance costs	(150)	(252)
Net carrying amount	$ 62,085	$ 64,530

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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Face (par) amount of debt instrument at time of issuance.

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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, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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